iPhone voicemail notice outside cellular service, but no msg when in service area?
I always thought the red dot without a number means your Voicemail service is unavailable, not that you have Voicemail waiting.

I spend a lot of my time outside reception areas, or abroad with no roaming, &amp; I have that icon the entire time I'm away; whether or not I have voicemail waiting for me when I get back [usually I don't].