Hello,
I've also been struggling with getting the Zend Debugger to work inside eclipse PDT but finally it works! I made a tutorial of 7 page's describing the installation/use of the Zend Debugger on a local Wamp 1.7.4 PHP server.
You can download the tutorial together with a eclipse PHP project 'debugtester' from http://www.kinetiek.com/files/download/debugtester.zip.
regards, Mike