When using the later revisions of Hudson 1.257 or 1.259,

This is an issue with Hudson where it puts new jobs in queue waiting for the
next available executer for no reason. For some reason Hudson was not able to
generate an executor to run a new job automatically. Jobs just remained in the
queue waiting for the next available executor.

I am on Sun Solaris 5.11 snv_55b i86pc i386, using Glassfish 9.1_02 (build
b04-fcs). Ofcourse restarting Glassfish resolves the problem for the time being
and re-installing/re-configuring Glassfish from scratch resolves this issue for
a day or so, but this is not a permanent solution.

After further investigation, we decided to downgrade Hudson to an earlier
version (1.200). And since then the problem seem to have gone away.