Create an empty PHP project. Open the .project file and see the difference between your SVN Project:

The differences will be this:

<buildSpec>
<buildCommand>
<name>net.sourceforge.phpeclipse.parserbuilder</name>
<arguments>
</arguments>
</buildCommand>
</buildSpec>
<natures>
<nature>net.sourceforge.phpeclipse.phpnature</nature>
</natures>

Probably you will have anything in your SVN project.