is there a php debugging extension which uses zend debug protocol?

hiho@ll my current project is getting very complex and shared over many servers the problem now is debugging in such an environment for development i'm using zend studio what i now need is capability of remote debugging i was searching for it, but it seems that there is only zend platform which is able to communicate with zend studio, right? Q1: is there an alternative for zend platform (open source would be the best so i can modify it)? the only thing i need is remote debugging with zend. it found the zend debug protocol on the eclipse website, but it doesn't seem that there is an php extension which is able to use this protocol!? Q2: another possiblity would be using xdebug as the "debug server", but the problem is, i didn't find a free php ide which is able to use it. so my problem is the combiniation of the remote debugging server and the php ide i also tried to install eclipse using xdebug but i didn't get it run yet (any links, tutorials, manuals would be great) Q3: is it possible to use xdebug with zend studio? afaik not cause zend studio doesn't use dbgp ptorocol, right? Q4: i searched for free debugger extensions and xdebug seems very good, but i didn't find a free php ide for it!! anybody knows one, with remote debugging capabilities? thx@ll