how to control the microphone (Series60)?

At this time there are no APIs that control this type of hardware! Nokia and a developer work close together in order to overcome this problem! However, I would think that this needs an update on the SDK (or more)which I hope that Nokia will release if they manage to overcome this small detail! Lets hope that Nokia will anounce something soon!

where can i find official information from Nokia or Symbian about it?

thanks

The only place I could think of is the Symbian Developer forum, but I am sure you already asked there or the Nokia forum!