Comment 114 for bug 1104435

(In reply to comment #23)
> Pushed 2 fixes to master for this. Please give it a shot.

This one alone fixes it:
http://git.xfce.org/xfce/xfce4-session/commit/?id=ab391138cacc62ab184a338e237c4430356b41f9

The other might have impact on startup time if you have many apps. I don't know how much difference in time it is vfork vs fork, if any at all. I suppose it should be tested. vfork *migh* be noticeable faster (even if g_spawn_async is cleaner).