Eclipse: Subversive compare editor doesn't work with php files

I also had the problem mentioned above:

Whenever I attempt to compare my working file with the one in the repository, I get a blank screen or it hangs with the message "Initializing...". It doesn't work regardless of what perspective I'm in or if I compare with the base revision or the latest from the repository.

I'm using eclipse 3.6.1 with subversive 0.7.9

The Solution was update the pdt eclipse plugin:

There is a bug mentioned here https://bugs.eclipse.org/bugs/show_bug.cgi?id=326194 that has a workaround. Apparently it will be fixed in the next release, but you can add the update site http://download.eclipse.org/tools/pdt/updates/2.2/milestones to your eclipse installation and it should fix your compare editor.

Resource:
http://stackoverflow.com/questions/5060114/subclipse-problem-comparing-php-files