I've got the following error when execting maven2 from an build job with extra
options site-deploy.

[ERROR] BUILD ERROR
[INFO] ------------------------------------------------------------------------
[INFO] Internal error in the plugin manager executing goal
'org.apache.maven.plugins:maven-site-plugin:2.0-beta-6:site': Remote call failed
Java heap space
[INFO] ------------------------------------------------------------------------
[INFO] For more information, run Maven with the -e switch
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2 minutes 20 seconds
[INFO] Finished at: Wed Feb 18 15:34:26 CET 2009
[INFO] Final Memory: 39M/99M
[INFO] ------------------------------------------------------------------------
channel stopped
finished: FAILURE

This looks like a maven2 error, but I already specified -Xmx=512M as MAVEN_OPTS

Sometimes through this error also an servlet become out of heap space and
complete hudson is stalled. The only way to restart hudson is killal -9 java.