Before Apple's ARC, you would often have to manage memory semi-manually. Before operation queues, you would also have to manage setting up autorelease pools on new threads. If you didn't, you would get an error such as:
autoreleased with no pool in place - just leaking - break on objc_autoreleaseNoPool() to debug
However, the other day, I started getting these myself! I was a little shocked - what on earth was I doing that required an autorelease pool? Well, eventually I figured it out. It turns out that if you have custom +load() functions on your classes (these get called whenever the classes load - I use them for registering handlers and such), this is another situation in which you have to set up your own autorelease pool if you do any object creation.
So, in your +load() function (or, depending on what you are doing, in functions that +load calls), just wrap it with
Your Code Here
And it works!