According to Using PHPEclipse : Installation : Installing the DBG Debugger - Plog4u, you should use Eclipse version 3.1.2 instead
Friday, June 08, 2007
Thursday, June 07, 2007
According to http://en.wikibooks.org/wiki/Using_PHPEclipse_:_Installation_:_Installing_PHPEclipse, you need to restart eclipse with the -clean option after adding stuff to the extensions and plugins folder. Could be why things weren't working earlier today!