V8 stalling

["Thomas, Nathan" <nthomas@imps0014.us.dg.com>]

As usual, my attempts to find info about this in the archives failed...

My V8 has started having an intermitent stalling problem.  Out of the
blue a couple of times a month the car will start and then just stall
immediately.  No drama, the idle just dies off and the car stops running.
A secondary symptom occurs on about every 1 in 5 starts where the
idle will drop down fairly low and then catch itself and struggle back
up to normal levels (I say struggle, because it does sputter a bit
trying to come back up).  When it stalls, if I just restart it and keep my
foot on the gas for 5 seconds it'll run just fine.  It's only in that first 5 
seconds that the car seems unable to set the right idle.  

So, any BTDT's?  My first guess was a dirty ISV, but I was thrown by
the intermitent nature of the problem.  Any help is appreciated.

nate