In most cases, the enemy in Iraq collects munitions such as unexploded artillery shells—available by the truckload, and cheap—then rigs the shells to explode by one of several easy methods.I wonder if we have tried poisoning the well of cheap artillery shells yet.
In Vietnam it was not uncommon for the Vietcong to use our own weapons against us. We would air drop loads of grenades, etc. for our use and the VC would pick some of them up before we could get there. The solution to this is was to booby trap some drops. Normal grenades have a fuze time around 5 seconds. The booby grenades had no delay. So instead of blowing up the other guy, the booby grenade blew you up. We knew the trapped grenades, but the VC didn't. The VC learned you couldn't trust found weapons.
We should be able to do something similar with artillery fuzes. My guess is that the first step in making an IED is removing the old fuze so you can jury rig a new one. Make a booby fuze that will go off (and detonate the main charge) if removed. You would have IED makers blowing themselves up all over Iraq. It wouldn't bother our ordnance disposal guys because, unlike in the movies where you cut the red wire, we generally dispose of unexploded artillery shells by blowing them up.