I have been using my mpx220 for about a week now. To be honest, I miss my mpx200... I thought it was a better phone... but it didn't have 850MHz which was causing serious reception problems. Bluetooth is a bonus, but the 850MHz is why I switched.

Anyway, I want to use the SIM1 lock to lock my SIM card. On the mpx200, I just created my own 4 digit code and then any time I powered the phone up it would ask me for that code. Since the SIM card was under the battery, this made it impossible to steal the SIM card.

I tried to do the same on my mpx220 but it appears the SIM1 lock has already been entered... no it wasn't me and I have no idea what the code is. Thing is, I don't get prompted when I power up... so it must be some default code?!?! It's a Cingular SIM card. Anyone else ever encounter this?

As a side note... anyone know what SIM2 lock is used for?

Please please please don't respond with "Well, Cingular phones come locked... does anyone know if companies are selling unlock codes for mpx220s?" This has NOTHING to do with that topic.

I'm talking about settings->security->enable SIM lock

SIM1=1111
SIM2=2222

If you get any errors STOP and contact Cingular.

That did the trick! Thanks!

FYI To All: Note that the instructions above say if that doesn't work then STOP! and Call Cingular. When dealing with any SIM1 or SIM2 codes, if you put the wrong thing in too many times (3 I belive) it will Fry your SIM rendering it permanently useless. You will have to get a new SIM card. I am not directing this at anyone person, but just as a general FYI...

after 3 times you can call cingular and get the PUK code to unlock it.

after that it will permanently lock you out of the sim.