Team edit of project

I wonder, what is the best practice to team edit the project?
One project is developing by several teamworkers. We use SVN/GIT as VCS.
Because of binary nature of .vpp files, they can’t be merged, so all teamworker have to start new file almost for each diagram (a pack of diagrams).
Unfortunatelly, Visual Paradigm, can’t open several projects in one time.
So it’s very annoying to work in team with vpp files.
Any ideas, sugeestions?

As you are using SVN server, team operation on our project can achieve through our Teamwork Client (supported in Standard Edition or above). Our Teamwork Client helps you to perform conflict detection and resolution on the model data (checking down to property level). More details about perform team operation on SVN can be found at http://www.visual-paradigm.com/product/vpuml/provides/svn.jsp

User’s guide on how to perform team operation on SVN
http://www.visual-paradigm.com/support/documents/vpumluserguide/100/133/22779_workingwitht.html

Feel free to contact me if you require any further information.

Best regards,
Rain Wong