I searched about after magwo posted. There seem to be a number of forum threads dealing with a range of topics from the garbage collector, loadlevelasynch() and even a few related networking ones. All seem to point towards validation of Zumwalt's idea, in that in each case individuals suspect a threading bug. Has anyone poked around Novell's Bugzilla for candidate issues in Mono 1.2.5? Things like - Bug 347837 - Value of ThreadState not consistent perhaps? WTB: Ability to search Unity's bug tracking system.