If you want you can compile on any of the OSX platforms that are currently supported by ASP.
So OSX 10.5.x onwards.
I prefer to compile on Snow Leopard as that is my main machine but I have environments set up for Lion, Snow Leopard and Leopard.
You can use virtual environments using VMWare or Oracle VirtualBox.
Important thing is to get the correct version of XCode for your platform and to use QT 4.7.4.
Thereafter it is all about configuration and getting the *.pro file correct.
I have some scripts that I use to Make before building in XCode environment and also to Fix plugins after compilations so that the executable used is pointing athe ASP frameworks rather than looking for the QTones that are on your compiling machine.
Still learning after all these years!