[STUMP] transient frames

[Mostafa Razavi]

I've been reading up on window placement rules in StumpWM but there is a 
certain setup I haven't been able to achieve and I was wondering if 
someone can point me to the right direction (if it's possible at all). 
What I want is that a certain window show up in a transient frame that 
appears when the window shows up and goes away when the window is 
closed. The main window of the program is always there and full-screen, 
but the secondary window when called for should appear in a frame, say 
to the right of the screen consuming one third of the screen width. Is 
this setup possible?