Xdebug and Symfony2 breakpoints stopping execution then disconnecting

I am having trouble getting breakpoints to work with symfony2. I can set a breakpoint anywhere in app.php before it reaches:

$request = Request::createFromGlobals();

and the debugger works as expected.

If I set the breakpoints anywhere after this phpstorm stops the execution and loads the debugger. Info get loaded, then it blinks and then it says disconnected and the debug info is gone.

Does anyone have any idea why this would be happening?