Sprint touch pro2 - sim card missing

[djqwikcut]

I have a sprint TP2 which came with the SIM CARD installed.. I am under the impression we dont need the SIM card unless we go overseas (since sprint is CDMA). Once in a while I will click on the UPDATE PRL and then I will get a "SIM CARD IS MISSING" and the only way to resolve is a SOFT reset and THEN I can use the phone again.. THIS ONLY HAPPENS about 10% of the time when I press UPDATE PRL. any ideas???

Thanks..