diff --git a/changelog.html b/changelog.html
index b351cb7610..267fcc3109 100644
--- a/changelog.html
+++ b/changelog.html
@@ -55,6 +55,9 @@ Upcoming changes</a>
 <!-- Record your changes in the trunk here. -->
 <div id="trunk" style="display:none"><!--=TRUNK-BEGIN=-->
 <ul class=image>
+  <li class=rfe>
+    Make captcha support optional; remove LGPL jcaptcha
+    (<a href="http://issues.jenkins-ci.org/browse/JENKINS-9915">issue 9915</a>)
   <li class=bug>
   	Validate new view name relative to current context
   <li class=bug>
diff --git a/core/pom.xml b/core/pom.xml
index ad99af6d6a..f28da4cf3a 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -703,49 +703,6 @@ THE SOFTWARE.
       <artifactId>memory-monitor</artifactId>
       <version>1.5</version>
     </dependency>
-    <dependency>
-      <groupId>com.octo.captcha</groupId>
-      <artifactId>jcaptcha-all</artifactId>
-      <version>1.0-RC6</version>
-      <exclusions>
-        <exclusion>
-          <groupId>hsqldb</groupId>
-          <artifactId>hsqldb</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>hsqldb</groupId>
-          <artifactId>hsqldb</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>net.sf.ehcache</groupId>
-          <artifactId>ehcache</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>quartz</groupId>
-          <artifactId>quartz</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>xerces</groupId>
-          <artifactId>xercesImpl</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>xerces</groupId>
-          <artifactId>xmlParserAPIs</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>org.springframework</groupId>
-          <artifactId>spring</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>commons-dbcp</groupId>
-          <artifactId>commons-dbcp</artifactId>
-        </exclusion>
-        <exclusion>
-          <groupId>concurrent</groupId>
-          <artifactId>concurrent</artifactId>
-        </exclusion>
-      </exclusions>
-    </dependency>
     <dependency><!-- StAX implementation. See HUDSON-2547. -->
       <groupId>org.codehaus.woodstox</groupId>
       <artifactId>wstx-asl</artifactId>
diff --git a/core/src/main/java/hudson/Functions.java b/core/src/main/java/hudson/Functions.java
index 37e7406198..7be7a79727 100644
--- a/core/src/main/java/hudson/Functions.java
+++ b/core/src/main/java/hudson/Functions.java
@@ -34,6 +34,7 @@ import hudson.security.AccessControlled;
 import hudson.security.AuthorizationStrategy;
 import hudson.security.Permission;
 import hudson.security.SecurityRealm;
+import hudson.security.captcha.CaptchaSupport;
 import hudson.security.csrf.CrumbIssuer;
 import hudson.slaves.Cloud;
 import hudson.slaves.ComputerLauncher;
@@ -687,6 +688,10 @@ public class Functions {
         return ParameterDefinition.all();
     }
 
+    public static List<Descriptor<CaptchaSupport>> getCaptchaSupportDescriptors() {
+        return CaptchaSupport.all();
+    }
+
     public static List<Descriptor<ViewsTabBar>> getViewsTabBarDescriptors() {
         return ViewsTabBar.all();
     }
diff --git a/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java b/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java
index aea72440ac..34b586dca3 100644
--- a/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java
+++ b/core/src/main/java/hudson/security/HudsonPrivateSecurityRealm.java
@@ -35,6 +35,7 @@ import hudson.model.User;
 import hudson.model.UserProperty;
 import hudson.model.UserPropertyDescriptor;
 import hudson.security.FederatedLoginService.FederatedIdentity;
+import hudson.security.captcha.CaptchaSupport;
 import hudson.tasks.Mailer;
 import hudson.util.PluginServletFilter;
 import hudson.util.Protector;
@@ -92,9 +93,21 @@ public class HudsonPrivateSecurityRealm extends AbstractPasswordBasedSecurityRea
      */
     private final boolean disableSignup;
 
-    @DataBoundConstructor
+    /**
+     * If true, captcha will be enabled.
+     */
+    private final boolean enableCaptcha;
+
+    @Deprecated
     public HudsonPrivateSecurityRealm(boolean allowsSignup) {
+        this(allowsSignup, false, (CaptchaSupport) null);
+    }
+
+    @DataBoundConstructor
+    public HudsonPrivateSecurityRealm(boolean allowsSignup, boolean enableCaptcha, CaptchaSupport captchaSupport) {
         this.disableSignup = !allowsSignup;
+        this.enableCaptcha = enableCaptcha;
+        setCaptchaSupport(captchaSupport);
         if(!allowsSignup && !hasSomeUser()) {
             // if Hudson is newly set up with the security realm and there's no user account created yet,
             // insert a filter that asks the user to create one
@@ -111,6 +124,15 @@ public class HudsonPrivateSecurityRealm extends AbstractPasswordBasedSecurityRea
         return !disableSignup;
     }
 
+    /**
+     * Checks if captcha is disabled on signup.
+     *
+     * @return true if captcha is disabled on signup.
+     */
+    public boolean isEnableCaptcha() {
+        return enableCaptcha;
+    }
+
     /**
      * Computes if this Hudson has some user accounts configured.
      *
@@ -194,7 +216,7 @@ public class HudsonPrivateSecurityRealm extends AbstractPasswordBasedSecurityRea
             throw HttpResponses.error(SC_UNAUTHORIZED,new Exception("User sign up is prohibited"));
 
         boolean firstUser = !hasSomeUser();
-        User u = createAccount(req, rsp, true, formView);
+        User u = createAccount(req, rsp, enableCaptcha, formView);
         if(u!=null) {
             if(firstUser)
                 tryToMakeAdmin(u);  // the first user should be admin, or else there's a risk of lock out
diff --git a/core/src/main/java/hudson/security/SecurityRealm.java b/core/src/main/java/hudson/security/SecurityRealm.java
index 50af858006..1bb1ce40ea 100644
--- a/core/src/main/java/hudson/security/SecurityRealm.java
+++ b/core/src/main/java/hudson/security/SecurityRealm.java
@@ -23,9 +23,6 @@
  */
 package hudson.security;
 
-import com.octo.captcha.service.CaptchaServiceException;
-import com.octo.captcha.service.image.DefaultManageableImageCaptchaService;
-import com.octo.captcha.service.image.ImageCaptchaService;
 import groovy.lang.Binding;
 import hudson.ExtensionPoint;
 import hudson.DescriptorExtensionList;
@@ -35,6 +32,7 @@ import hudson.model.AbstractDescribableImpl;
 import hudson.model.Descriptor;
 import jenkins.model.Jenkins;
 import hudson.security.FederatedLoginService.FederatedIdentity;
+import hudson.security.captcha.CaptchaSupport;
 import hudson.util.DescriptorList;
 import hudson.util.PluginServletFilter;
 import hudson.util.spring.BeanBuilder;
@@ -57,13 +55,13 @@ import org.springframework.context.ApplicationContext;
 import org.springframework.web.context.WebApplicationContext;
 import org.springframework.dao.DataAccessException;
 
-import javax.imageio.ImageIO;
 import javax.servlet.Filter;
 import javax.servlet.FilterConfig;
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpSession;
 import javax.servlet.http.Cookie;
 import java.io.IOException;
+import java.util.List;
 import java.util.Map;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -127,6 +125,11 @@ import java.util.logging.Logger;
  * @see PluginServletFilter
  */
 public abstract class SecurityRealm extends AbstractDescribableImpl<SecurityRealm> implements ExtensionPoint {
+    /**
+     * Captcha Support to be used with this SecurityRealm for User Signup
+     */
+    private CaptchaSupport captchaSupport;
+
     /**
      * Creates fully-configured {@link AuthenticationManager} that performs authentication
      * against the user realm. The implementation hides how such authentication manager
@@ -236,6 +239,18 @@ public abstract class SecurityRealm extends AbstractDescribableImpl<SecurityReal
         return req.getContextPath()+"/";
     }
 
+    public CaptchaSupport getCaptchaSupport() {
+        return captchaSupport;
+    }
+
+    public void setCaptchaSupport(CaptchaSupport captchaSupport) {
+        this.captchaSupport = captchaSupport;
+    }
+
+    public List<Descriptor<CaptchaSupport>> getCaptchaSupportDescriptors() {
+        return CaptchaSupport.all();
+    }
+
     /**
      * Handles the logout processing.
      *
@@ -324,35 +339,29 @@ public abstract class SecurityRealm extends AbstractDescribableImpl<SecurityReal
         throw new UnsupportedOperationException();
     }
 
-    /**
-     * {@link DefaultManageableImageCaptchaService} holder to defer initialization.
-     */
-    public static final class CaptchaService {
-        public static ImageCaptchaService INSTANCE = new DefaultManageableImageCaptchaService();
-    }
-
     /**
      * Generates a captcha image.
      */
     public final void doCaptcha(StaplerRequest req, StaplerResponse rsp) throws IOException {
-        String id = req.getSession().getId();
-        rsp.setContentType("image/png");
-        rsp.addHeader("Cache-Control","no-cache");
-        ImageIO.write( CaptchaService.INSTANCE.getImageChallengeForID(id), "PNG", rsp.getOutputStream() );
+        if (captchaSupport != null) {
+            String id = req.getSession().getId();
+            rsp.setContentType("image/png");
+            rsp.addHeader("Cache-Control", "no-cache");
+            captchaSupport.generateImage(id, rsp.getOutputStream());
+        }
     }
 
     /**
      * Validates the captcha.
      */
     protected final boolean validateCaptcha(String text) {
-        try {
+        if (captchaSupport != null) {
             String id = Stapler.getCurrentRequest().getSession().getId();
-            Boolean b = CaptchaService.INSTANCE.validateResponseForID(id, text);
-            return b!=null && b;
-        } catch (CaptchaServiceException e) {
-            LOGGER.log(Level.INFO, "Captcha validation had a problem",e);
-            return false;
+            return captchaSupport.validateCaptcha(id, text);
         }
+
+        // If no Captcha Support then bogus validation always returns true
+        return true;
     }
 
     /**
diff --git a/core/src/main/java/hudson/security/captcha/CaptchaSupport.java b/core/src/main/java/hudson/security/captcha/CaptchaSupport.java
new file mode 100644
index 0000000000..8fc07b4c6d
--- /dev/null
+++ b/core/src/main/java/hudson/security/captcha/CaptchaSupport.java
@@ -0,0 +1,65 @@
+/*
+ * The MIT License
+ * 
+ * Copyright (c) 2011, Winston.Prakash@oracle.com
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package hudson.security.captcha;
+
+
+import hudson.DescriptorExtensionList;
+import hudson.ExtensionPoint;
+import hudson.model.AbstractDescribableImpl;
+import hudson.model.Descriptor;
+import hudson.model.Hudson;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+
+/**
+ * Extension point for adding Captcha Support to User Registration Page {@link CaptchaSupport}.
+ *
+ * <p>
+ * This object can have an optional <tt>config.jelly</tt> to configure the Captcha Support
+ * <p>
+ * A default constructor is needed to create CaptchaSupport in
+ * the default configuration.
+ *
+ * @author Winston Prakash
+ * @since 1.416
+ * @see CaptchaSupportDescriptor
+ */
+public abstract class CaptchaSupport extends AbstractDescribableImpl<CaptchaSupport> implements ExtensionPoint {
+    /**
+     * Returns all the registered {@link CaptchaSupport} descriptors.
+     */
+    public static DescriptorExtensionList<CaptchaSupport, Descriptor<CaptchaSupport>> all() {
+        return Hudson.getInstance().<CaptchaSupport, Descriptor<CaptchaSupport>>getDescriptorList(CaptchaSupport.class);
+    }
+    
+    abstract public  boolean validateCaptcha(String id, String text); 
+    
+    abstract public void generateImage(String id, OutputStream ios) throws IOException;
+
+    public CaptchaSupportDescriptor getDescriptor() {
+        return (CaptchaSupportDescriptor)super.getDescriptor();
+    }
+}
diff --git a/core/src/main/java/hudson/security/captcha/CaptchaSupportDescriptor.java b/core/src/main/java/hudson/security/captcha/CaptchaSupportDescriptor.java
new file mode 100644
index 0000000000..99e5b7b5d7
--- /dev/null
+++ b/core/src/main/java/hudson/security/captcha/CaptchaSupportDescriptor.java
@@ -0,0 +1,37 @@
+/*
+ * The MIT License
+ *
+ * Copyright (c) 2011, Winston.Prakash@oracle.com
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package hudson.security.captcha;
+
+import hudson.model.Descriptor;
+
+/**
+ * {@link Descriptor} for {@link CaptchaSupport}.
+ *
+ * @author Winston Prakash
+ * @since 2.0.1
+ */
+public abstract class CaptchaSupportDescriptor extends Descriptor<CaptchaSupport> {
+    // so far nothing different from plain Descriptor
+    // but it may prove useful for future expansion
+}
diff --git a/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/config.jelly b/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/config.jelly
index 454d733f2e..8cc15a8f9e 100644
--- a/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/config.jelly
+++ b/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/config.jelly
@@ -23,9 +23,25 @@ THE SOFTWARE.
 -->
 
 <?jelly escape-by-default='true'?>
-<j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
-	<f:entry title="" help="/help/security/private-realm/allow-signup.html">
-	  <f:checkbox name="privateRealm.allowsSignup" checked="${h.defaultToTrue(instance.allowsSignup())}"
-            title="${%Allow users to sign up}"/>
+<j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson"
+  xmlns:f="/lib/form">
+  <f:entry title="" help="/help/security/private-realm/allow-signup.html">
+    <f:checkbox name="privateRealm.allowsSignup" checked="${h.defaultToTrue(instance.allowsSignup())}" title="${%Allow users to sign up}" />
   </f:entry>
-</j:jelly>
\ No newline at end of file
+  <j:if test="${size(h.captchaSupportDescriptors) gt 0}">
+    <f:entry>
+      <f:checkbox name="privateRealm.enableCaptcha" checked="${h.defaultToTrue(instance.isEnableCaptcha())}"
+        title="${%Enable captcha on sing up}" />
+    </f:entry>
+    <f:dropdownList name="privateRealm.captchaSupport" title="${%Captcha Support}">
+      <!-- Loop through available Captcha Support Descriptors -->
+      <j:forEach var="descriptor" items="${h.captchaSupportDescriptors}" varStatus="loop">
+        <f:dropdownListBlock title="${descriptor.displayName}" value="${loop.index}"
+          selected="${descriptor==instance.captchaSupport.descriptor}" staplerClass="${descriptor.clazz.name}">
+          <!-- Include config.jelly for this Captcha Support -->
+          <st:include page="${descriptor.configPage}" from="${descriptor}" optional="true" />
+        </f:dropdownListBlock>
+      </j:forEach>
+    </f:dropdownList>
+  </j:if>
+</j:jelly>
diff --git a/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/signup.jelly b/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/signup.jelly
index 3246288fc8..656e96c3c9 100644
--- a/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/signup.jelly
+++ b/core/src/main/resources/hudson/security/HudsonPrivateSecurityRealm/signup.jelly
@@ -27,5 +27,5 @@ THE SOFTWARE.
 -->
 <?jelly escape-by-default='true'?>
 <j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
-  <local:_entryForm host="${app}" title="${%Sign up}" action="createAccount" captcha="${true}" xmlns:local="/hudson/security/HudsonPrivateSecurityRealm" />
-</j:jelly>
\ No newline at end of file
+  <local:_entryForm host="${app}" title="${%Sign up}" action="createAccount" captcha="${it.isEnableCaptcha()}" xmlns:local="/hudson/security/HudsonPrivateSecurityRealm" />
+</j:jelly>
diff --git a/war/src/main/webapp/help/security/private-realm/allow-signup.html b/war/src/main/webapp/help/security/private-realm/allow-signup.html
index ceaeec8d69..124f422cba 100644
--- a/war/src/main/webapp/help/security/private-realm/allow-signup.html
+++ b/war/src/main/webapp/help/security/private-realm/allow-signup.html
@@ -2,7 +2,10 @@
   By default, Jenkins allows users to create accounts by themselves, via the "sign up" link on the top right shoulder of the page.
   But if you'd like to prevent random users from creating accounts, and instead tightly control how user accounts are created,
   uncheck this box.
-
   <p>
   When this checkbox is unchecked, someone with the administrator role would have to create accounts. 
-</div>
\ No newline at end of file
+  <p>
+  By default, Jenkins does not use captcha verification if the user creates an account by themself.
+  If you'd like to enable captcha verification, install a captcha support plugin, e.g. the Jenkins
+  <a href="https://wiki.jenkins-ci.org/display/JENKINS/JCaptcha+Plugin">JCaptcha Plugin</a>.
+</div>