unlock Nokia 6230b (US)

I would appreciate help unlocking a Nokia 6230b on the US Cingular network, IMEI 353372001390364.
Thank you!
Bill

 

#pw+188 494 704 666 203+1#

1. Insert a non accepted sim, most times it will show "Phone Restricted"
2. Press the UNDO option
3. You should see a box that says enter restriction code.
4. Enter the code given and then press (OK)

 

Thanks for the help!

 

Unfortunately the phone still says "Phone restricted". IS there any other code to try or information you would need?