Wow, crash isn't good.

This is exactly the bug I mentioned on the getting started page and is an Eclipse bug issue that I reported and has been fixed in the latest Milestone release. The best way to get the plugins is to use the (completely non-advertised) Eclipse Ganymede release plugin site. That together with the oAW and metaABM sites should be all you need.
Distro:
http://download.eclipse.org/eclipse/downloads/drops/S-3.4M4-200712131700/macPlatform.php[In general, for milesstone releases go to the platform download page, find the 3.xMx page and find the Mac SDK.]
Plugins:
http://download.eclipse.org/releases/ganymede/staging/http://www.eclipse.org/gmt/oaw/download/http://eclipse.metaabm.org/updates/release/Let me know if that works for you as well and I'll update the Leopard instructions with these specifics.