To be honest I couldn't tell you why it was causing the issue. As for your problem, all the documentation I have seen on using the GC "hack" says that it is just that a hack. You're not supposed to be able to trigger GC and as such that it should only be used as a tool in testing. My advice would be to step back for a min and find out what is actually causing the memory leak you're having. At best the GC hack would be a bandaid for the real issue at hand. I realize we all have deadlines to make, but if your memory leak is that bad it would seem to make sense that the greater good would be served by fixing what is causing the leak.