If you're a Zend Studio IDE user and are having trouble on the latest release of Apple's operating system (Snow Leopard), Davey Shafik might be able to help. In these two posts he walks you through how you can fix a crashing issue and a problem that comes up when selecting text.
For the first problem:
OSX Leopard, it has seemed for a while, like the app was decaying - growing progressively crashier the more I used it. Literally, to the point where I could use it. I think, however, I have solved the issue. [...] This just explicitly makes it use JVM 1.5, which is, after all, what it was built for.
And for the second (text selection):
If you are still using Zend Studio 5.5, and recently upgrade to Snow Leopard, you will have spotted pretty quickly there is a pretty severe display bug when selecting text. The reason for this, is that Snow Leopard only ships with Java 1.6 and 1.3 (wtf?) [...] It essentially comes down to this: Grab the Java 1.5 JDK from Leopard (original) and then tell OSX to use the 32bit version by default.
You can find out more information on the cause of this problem here.