Hello Kent:

I don't know what system or server level you are running but this looks
a little bit like APAR IC15588 (this is the AIX version of the APAR).
If this is the case you would see additional CPU utilization.  If you
can run the trace mentioned in the APAR when the problem happens and you
see the same trace messages over and over again showing expired entries
in the schedule pending table then this is the problem you are seeing.

Hope this helps.
David Bohm, ADSM technical support.