Occasional 'Queue Full' errors even though queue is empty

[heat23]

I have JBoss AS 4.0.4 GA and Messaging 1.0.0. Sometimes when I attempt to put a message on queue A or queue B, I get a 'Queue Full' error even though the message count is 0. I am using an out of the box configuration. Any ideas?

[timfox]

Please post the exception report.