With 1.339, and latest email-ext, all attempts to save projects fail as follows. If I disable email-ext the problem goes away.

Failed to parse form data. Please report this problem as a bug
JSON={"":["select","Failure",""],"artifactId":"antfarm-trunk","builder":

{"kind":"hudson.tasks.Shell$DescriptorImpl","shell":"#!/bin/sh\nbash x.sh\n","stapler-class":"hudson.tasks.Shell"}

,"cloverReportPath":"","coberturaReportPath":"","customWorkspace":

{"directory":"/u1/rlp-trunk"}

,"description":"","groupId":"basistech","hasSlaveAffinity":

{"slave":"antfarm"}

,"hudson-plugins-cigame-GamePublisher":false,"hudson-plugins-emailext-ExtendedEmailPublisher":false,"hudson-plugins-sonar-SonarPublisher":false,"hudson-triggers-SCMTrigger":

{"scmpoll_spec":"@midnight"}

,"installationName":"","javaVersion":"","jdk":"JDK16","jobAdditionalProperties":"","jobProperty0":{},"logrotate":

{"logrotate_days":"","logrotate_nums":"1"}

,"mailer_Failure_body":"$PROJECT_DEFAULT_CONTENT","mailer_Failure_configured":"true","mailer_Failure_includeCulprits":false,"mailer_Failure_recipientList":"","mailer_Failure_sendToDevelopers":true,"mailer_Failure_sendToRecipientList":true,"mailer_Failure_subject":"$PROJECT_DEFAULT_SUBJECT","mailer_Fixed_body":"$PROJECT_DEFAULT_CONTENT","mailer_Fixed_configured":"false","mailer_Fixed_includeCulprits":false,"mailer_Fixed_recipientList":"","mailer_Fixed_sendToDevelopers":true,"mailer_Fixed_sendToRecipientList":true,"mailer_Fixed_subject":"$PROJECT_DEFAULT_SUBJECT","mailer_Still-Failing_body":"$PROJECT_DEFAULT_CONTENT","mailer_Still-Failing_configured":"false","mailer_Still-Failing_includeCulprits":false,"mailer_Still-Failing_recipientList":"","mailer_Still-Failing_sendToDevelopers":true,"mailer_Still-Failing_sendToRecipientList":false,"mailer_Still-Failing_subject":"$PROJECT_DEFAULT_SUBJECT","mailer_Still-Unstable_body":"$PROJECT_DEFAULT_CONTENT","mailer_Still-Unstable_configured":"false","mailer_Still-Unstable_includeCulprits":false,"mailer_Still-Unstable_recipientList":"","mailer_Still-Unstable_sendToDevelopers":true,"mailer_Still-Unstable_sendToRecipientList":false,"mailer_Still-Unstable_subject":"$PROJECT_DEFAULT_SUBJECT","mailer_Success_body":"$PROJECT_DEFAULT_CONTENT","mailer_Success_configured":"false","mailer_Success_includeCulprits":false,"mailer_Success_recipientList":"","mailer_Success_sendToDevelopers":true,"mailer_Success_sendToRecipientList":false,"mailer_Success_subject":"$PROJECT_DEFAULT_SUBJECT","mailer_Unstable_body":"$PROJECT_DEFAULT_CONTENT","mailer_Unstable_configured":"false","mailer_Unstable_includeCulprits":false,"mailer_Unstable_recipientList":"","mailer_Unstable_sendToDevelopers":true,"mailer_Unstable_sendToRecipientList":true,"mailer_Unstable_subject":"$PROJECT_DEFAULT_SUBJECT","mavenInstallationName":"","mavenOpts":"","name":"rlp-trunk-antfarm","projectBinDir":"","projectDescription":"","projectName":"antfarm
trunk","projectSrcDir":"trunk","projectSrcEncoding":"","projectVersion":"","project_content_type":"default","project_default_content":"$DEFAULT_CONTENT","project_default_subject":"$DEFAULT_SUBJECT","recipientlist_recipients":"","reuseReports":false,"scm":{"":"auto","doRevert":true,"excludedCommitMessages":"","excludedRegions":"","excludedRevprop":"","excludedUsers":"","locations":

{"local":"","remote":"http://svn.basistech.net/engineering/views/trunk"}

,"useUpdate":true,"value":"2"},"scmBuilds":false,"skipIfBuildFails":false,"snapshotDependencyBuilds":false,"surefireReportsPath":"","timerBuilds":true,"useSonarLight":true}

net.sf.json.JSONException:
JSONObject["hudson-plugins-emailext-ExtendedEmailPublisher"] is not a
JSONObject.
at net.sf.json.JSONObject.getJSONObject(JSONObject.java:1734)
at hudson.util.DescribableList.rebuild(DescribableList.java:139)
at hudson.model.Project.submit(Project.java:195)
at hudson.model.FreeStyleProject.submit(FreeStyleProject.java:97)
at hudson.model.Job.doConfigSubmit(Job.java:967)
at hudson.model.AbstractProject.doConfigSubmit(AbstractProject.java:527)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:185)
at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:101)
at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:54)
at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:74)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:492)
at org.kohsuke.stapler.MetaClass$6.doDispatch(MetaClass.java:180)
at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:492)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:408)
at org.kohsuke.stapler.Stapler.service(Stapler.java:117)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:45)
at winstone.ServletConfiguration.execute(ServletConfiguration.java:249)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:335)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:378)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:94)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:86)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:47)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
at hudson.security.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:166)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:173)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:66)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:244)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:150)
at java.lang.Thread.run(Thread.java:619)