force a mobile to re-register @ the MSC

I need to figure out how to force all mobiles in our coverage area to consistently re-register in the VLR. There are typically not more that 200 subscribers. This is a very unusual application and all of our hardware (field and switch) is proprietary. Generic answers are fine.

Typically you can change the amount of time it takes for the VLR to flag you as idle and detach you, forcing the phone to re-register the next time the customer uses their phone. Im afraid that having every customer detach and re-attach their IMSI every few seconds will overload our processors and create a back log of event entries.

Aside from a HHO or power cycle I dont know how to force a mobile to re-register in the MSC.

All thoughts and ideas are appreciated.