iPhone + new SIM -> failing?

[ct2k7]

Hi, I've been sent a new SIM by O2 due to a change in my mobile tariff, Pay Monthly -> Pay As You Go.

I have an iPhone 1st generation from April 08

And as of writing this, I was just about to take a pic and iPhone 3.1.3 decides to install, but this is something I've noticed: both SIMs are slightly different.

The older card has a bigger chip, smaller one has a smaller chip. Anyone know the reason for difference in size?

Anyway,

whenever I put the phone into airplane mode or even reboot it, the phone asks me to connect to iTunes. Today, it happened in the most inconvenient place just before I was to make a call.

On connecting to iTunes, I have to agree to the terms and conditions before it activates the device. iTunes then tells me that the iPhone has been successfully unlocked.

Any ideas?

 

[jav6454]

regardless of the form factor of the gold, all SIMs will work in an iPhone. If it doesn't it means you got a defective one. Just call O2 and let them know about it.

 

[ct2k7]

I've got another SIM, same thing keeps happening with it. Weird thing is that it doesn't happen with the bigger chip SIMs, only the newer smaller ones.