Apps Error Export Signed Application Package

[firblazer]

Hi I am trying to export signed application package.

I click on Android Tools, export signed application package, filled in the details and click on finish. I get:

Errors running builder 'Java Builder' on project 'myProject'

[HIGH]
java.lang.NullPointerException
at org.eclipse.jdt.internal.core.builder.ClasspathJar.equals(ClasspathJar.java:141)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.hasClasspathChanged(JavaBuilder.java:533)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.build(JavaBuilder.java:179)
at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:733)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:206)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:246)
at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:299)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:302)
at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:358)
at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:381)
at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:143)
at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:241)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:53)
[/HIGH]

Please help. Thanks