Every now and again we get a NullPionterException while uploading our ears after a build has ran. Most of the time it works but seemingly at random periods the upload fails with this stacktrace:

[SCP] Connecting to someserver
[SCP] remote folderPath tas,local file:MyProject-SNAPSHOT.ear
ERROR: Failed to upload files
4: java.lang.NullPointerException
at com.jcraft.jsch.ChannelSftp._put(ChannelSftp.java:599)
at com.jcraft.jsch.ChannelSftp.put(ChannelSftp.java:461)
at com.jcraft.jsch.ChannelSftp.put(ChannelSftp.java:431)
at be.certipost.hudson.plugin.SCPSite.upload(SCPSite.java:201)
at be.certipost.hudson.plugin.SCPRepositoryPublisher.perform(SCPRepositoryPublisher.java:126)
at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:36)
at hudson.model.AbstractBuild$AbstractRunner.perform(AbstractBuild.java:582)
at hudson.model.AbstractBuild$AbstractRunner.performAllBuildStep(AbstractBuild.java:563)
at hudson.maven.MavenModuleSetBuild$RunnerImpl.post2(MavenModuleSetBuild.java:594)
at hudson.model.AbstractBuild$AbstractRunner.post(AbstractBuild.java:528)
at hudson.model.Run.run(Run.java:1266)
at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:304)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:122)
Caused by: java.lang.NullPointerException
Email was triggered for: Unstable

The ear being uploaded is around 55 MB.