already wrote about this two weeks ago.
the client wil handle it this way:
1. check if address is within own address book -> green
2. if account exist within blockchain -> yellow
3. don't exist within blockchain -> red
simple visual control.
Some ppl confuse green and red...

Yes, not insignificant percentage of people are color blind. We need a specific dialog box in the red case, defaulted to NOT send.
James
P.S. What version should peercover run? 4.8 or 4.9, if 4.9 where is it?