Has anyone cut O2 sim to fit micro iphone 4/ipad

[teadigger]

Here is the problem, did a deal with O2 for unlimited data package ect, which was a non iphone contract, and pay £9.00 month. Just phoned O2 to say can I swap sim to a micro sim for iphone 4 (Which if the money tree blossoms will come direct from apple), guess what they said oh you should not be using that with sim with a iphone, you should have our £35 contract. Extra charges may be incurred ect, which I have never got. And surely thats up to me I pay for the thing its up to me how i use it.
Any how can I cut my current sim down to the size of a micro sim, had a go at an old sim card and no wiring goes into the plastic has anyone tried this on a ipad.

Just like to shove it to 02 money grabbing Ba****ds.
Many thanks TEADIGGER
oh forgot to say sim has been in 3g and now 3gs