I had the same problem. I run Ubuntu 12.04 64 bit (and a gforce graphics card which generated it's own long trail of problems for running minecraft). It works now for me though. I had the same problem as with normally starting minecraft in the beginning, minecraft would just crash. Had to download and deploy the newest lwjgl libraries in ~/.minecraft.
When I copied those .jar files and the native folder from my ~/.minecraft to forge/mcp/jars/bin, it did work: I can hit run in eclipse and have the minecraft client popping up.