If I'm driving and on a call (Calling someone else) where the phone is ringing can my phone still handoff? Also, if my phone is receiving an incoming call and it switches towers will it forward the call to VM? I heard someone say a long time ago that it will drop the call? Also my bro's new mm7400 has an option where you can reject an incoming call- sending it directly to voicemail. Anyway the software in my phone (PM-8200) be updated to have this feature?
I'm guessing you have Sprint CDMA service. With CDMA service you could be operating on several different towers at one time. So you should not drop the call when you hand off. The exception to this is if you were receiving a call and handed off to a roaming partner or different carrier. I'm not sure about the question on sending directly to voice mail, when I worked for Sprint none of the phones would do that, however with Verizon they all will. In general if your phone is not doing that now it probably will not be enabled unless it is updated in a future software update, which is unlikely.
No, I don't think so, otherwise GSM/TDMA phones would drop a lot of calls while the phone was making/receiving a call. Only difference, as far as I know, is that with GSM/TDMA the ringing call is just handed off hard instead of soft, like with CDMA.