on all about symbian someone couldn't make any phone calls ([url=your phone could be a little confused]here[/url]). some other guy told him to hold # while restarting the phone. the phone should ask him whether he wants to "change outgoing phone line".
Now, what i'm trying to say probably won't help but it might be worth a try. your phone could be a little confused.
hold the # while you reboot the phone and change the outgoing phone line if the phone asks you. restart again. i *hope* the message disappeared now.
if you cannot make phone calls after following the above instructions, set the outgoing phone line back to the original. you can do that by holding # while restarting the phone.
good luck.

gee thanx you're awesome

"change outgoing phone line" comes up if you are on standby screen and keep your finger on the # key....

People on Orange network can have 2 seperate phone lines on 1 simcard. all this does is swap between the 2 phone lines!!!!!