Modifying the dial-up screen?
 

I'm not sure if this is correct place for this topic.

Is it possible to change the "mute" button to "record on/off" button in the dialing screen.

I would want to record my phone calls. It would be so useful sometimes. The recording program shouldn't be too heavy. Smoothly running tiny program would be so so awesome.

Could there also be some kind of a tab in the settings for this recording? Including location of the files, sound quality, start recording automaticly no/yes and this kind of stuff.

Maybe editing the rom or the registry? I'm so noob in both of those so I'm hoping someone else likes this idea too.
My phone is Samsung Omnia 2

My english sounds hilarious, sorry

Any kind of advice is accepted.