It's likely not related to any idle code -- that code doesn't store anything in memory, it just looks at a single value. Out of memory problems tend to arise after a long delay because it is only after a long period of time that enough items can accumulate to cause a memory problem.

Perhaps it is related to Sun caching all IPs in memory forever. We'll experiment with changing that setting (if it is changable?) and see how that helps.

Of course, we're always on the lookout for memory leaks.

Regarding corruption detection -- right now the download code is not structured in a way that we can easily determine which host caused corruption. This will be done at some point, but for now LimeWire just tries to download six times, and if it's still corrupted after the sixth attempt it will give up.