Has anyone heard of at least a similar problem with a treo 600 as outlined below?

(long version)
Recently I woke up and there were no new messages on my phone... this while being a little unusual didnt really worry me (I get FaceBook to send me texts whenever some people post on their wall... which happens a lot... particularly when I am asleep). Later in the day on the couple of hour drive to the ortodontist's to get my brother's braces updated I noticed that my phone was saying it had no service... not even sos... which is a little odd... but as we were in the middle of an national park? I was not unduly worried... however when we got to maitland and i was waiting in the car for dad and my brother (the waiting room was full) I pulled out my phone... and low and behold it still didnt have service.... Now I was beginning to wonder... and so turned off the phone capabilities and removed the sim to see if replacing it would make aa difference... It didn't... So I looked at the contacts on the back of the sim... and wondered if due to having gone through the wash (in a different phone) that they had corroded a little... so I tried to clean them with what was in the car... my shirt... a maccas napkin... but it still didnt work... so when I got home I tried it with some cotton buds and glasses cleaner... then one time when I tried it it worked... but only for a few seconds.. so I am not sure if there was a little residue that was improving the contact... Anyway I then tried it in a different phone... and it worked first go... and tried the sim from that phone in my Treo... it didn't work...

(short version)
My Treo 600 has stopped recognizing sim cards properly... It will see that there is one... But it will not connect to the network at all... it just says no service...

This morning when I have turned it on it has worked for a minute or two... and then gone back to how it was... so not sure what that means...

If anyone else has had a similar problem could they please mention... Just so I know if it is just a problem with my phone...