Given the stack-trace, you have used Java 7 to run Jenkins. (The sort algorithm in Arrays.sort was changed in Java 7.)

Is the issue reproduced with a recent version of Jenkins?

I think it is no longer an issue, we did not see this problem a long time.

I am having the same issue. I am using jenkins version 1.512 with java 1.7.0_21. It does not happen for all projects but for few. Can someone shed some light on this?
Thanks.

@rakesh
Can you give the stack-trace of your exception?
It is probably a bit different and it is needed to fix the problem.

Hi evernat,
Here it is..Note this happens at the end of the build and so it cant trigger downstream builds.

[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 21.444s
[INFO] Finished at: Wed May 22 16:47:59 EDT 2013
[INFO] Final Memory: 9M/240M
[INFO] ------------------------------------------------------------------------
[JENKINS] Archiving /bbnms/jenkins/R1310/jenkins/workspace/lightspeed-pom/lightspeed-pom/pom.xml to /bbnms/jenkins/R1310/jenkins/jobs/lightspeed-pom/modules/com.att.bbnms.lightspeed$lightspeed-pom/builds/2013-05-22_16-47-33/archive/com.att.bbnms.lightspeed/lightspeed-pom/1310-SNAPSHOT/lightspeed-pom-1310-SNAPSHOT.pom
Waiting for Jenkins to finish collecting data
channel stopped
FATAL: Comparison method violates its general contract!
java.lang.IllegalArgumentException: Comparison method violates its general contract!
at java.util.TimSort.mergeHi(TimSort.java:868)
at java.util.TimSort.mergeAt(TimSort.java:485)
at java.util.TimSort.mergeForceCollapse(TimSort.java:426)
at java.util.TimSort.sort(TimSort.java:223)
at java.util.TimSort.sort(TimSort.java:173)
at java.util.Arrays.sort(Arrays.java:659)
at java.util.Collections.sort(Collections.java:217)
at hudson.tasks.BuildTrigger.execute(BuildTrigger.java:199)
at hudson.model.AbstractBuild$AbstractBuildExecution.cleanUp(AbstractBuild.java:739)
at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.cleanUp(MavenModuleSetBuild.java:975)
at hudson.model.Run.execute(Run.java:1620)
at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:477)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:237)

ok, it's probably a regression in recent Jenkins which gives almost the same exception when using Java 7, so reopening the issue.

The problem is in the sort of downstream dependencies of a job:
https://github.com/jenkinsci/jenkins/blob/master/core/src/main/java/hudson/tasks/BuildTrigger.java#L199

But I don't know what has caused this and how to fix it.

Looks like a duplicate of JENKINS-17247