this is hopefully something simple but... Eclipse has been working relatively fine for everything except deploying to GAE.
I can run my GAE app locally, but when I
I had the same problem and was able to deploy successfully after forcing Eclipse to use the JRE within my SDK directory (Win 7 64bit). To force Eclipse to use a particular JRE see this. It seems that the JVM that Eclipse uses, the JVM that app engine spawns, & the JVM that appconfig uses should all be the same. Hope this helps w/ your situation as well.