> Maybe apple doesn't support applications written for an older version
> of the OS, this would be sad.

It's probably old enough that it's a PowerPC app and not an Intel one, and yes Apple dropped support for running PowerPC apps on current versions of OSX.

It used to be that Macs used a totally different kind of CPU than the Intel chips. Apple had a translation/emulation layer called 'Rosetta' that would enable them to run but that's been dropped as of OSX 10.7 I think.

- Michael