Scam and Phishbusters → [Scam] voice mail replay. scam?

This just happened today. A family member got a voice mail on their cell phone, seemingly from a friend asking to "call me back" but from an unfamiliar number. Checking with that friend at their real number revealed that the voice mail was in fact a replay of an older voice mail from a few weeks ago. Sounds like a tricky scam, thought I'd ask.

Since I'm asking one question anyways, here is a second. Last autumn guests came to visit for just a couple of hours. While here, they received scam-sounding calls on their cell phones but the calls were directed to members of our household. It was kind of concerning, should I be worried?

First question... Scammers love to get into barely secured voice mail, copy the contents, some slight editing, and reuse it.
»www.fcc.gov/consumers/gu ··· -hacking

For the second question... Not quite like the question, but a malware with full access to the phone's data and GPS to properly create the scam.
Interesting article here with a GPS malware. Fake traffic ticket notification.
»www.oregonlive.com/commu ··· ing.html

904-344-1025 and 904-674-6133, some of the numbers used in the scam. No doubt they are using voip to spoof numbers.