I did - I transferred the ones on my old SIM card to my new phone, then deleted the ones from the old SIM, then put it back in my old phone and copied the numbers from the phone to the SIM. Then I put that back in my new phone and copied the numbers there (it had a bigger memory).
If that doesn't make sense, let me know and I'll try to word it better!
OK, I've put my SIM in my new phone and moved all the no's on it to the new phone's memory. I've now put the SIM back in my old phone (Nokia 3330), but can't work out how to get the no's still in that phone's memory onto the SIM card. Maybe the old phone can't do it?
I think you view the number, bring up the options, one of which is copy. You then get the option to copy it to SIM or phone. Min'es not the same phone as yors at all though but it's worked on the last 2 phones I've had.