I know this is futile and it wont change the outcome of this thread (unless someone else knows more) but I think the reasoning is a little flawed.
Id be more inclined to say this is a bug in the phone/jvm/ams. I would imagine there would/should be an attribute that is placed in the JAD file, similar to the one that controls how the red key is to be treated.
Other than that, this behaviour is interfering with the normal operation of the midlet. Users are supposed to be able to dial from within using the green key.