One possibility is that the six-year-old phone is an analog (AMPS) only phone. Six years ago, 1999, CDMA was just starting to roll out and relatively few manufacturer had phones out (Qualcomm, Sony and towards the end of the year Motorola and Samsung, IIRC). Right now Verizon Wireless is in the process of reducing their analog coverage to the minimum that they can get away with in preparation to shutting down the analog system once they are allowed.
Therefore, it is possible that the trouble making calls was that the area being visited had poor analog coverage, but Choreboy's relative's home area still as good analog coverage.
If this is case the technician still made an incorrect statement; either due to ignorance, or because of some policy that blames analog coverage woes on the phone rather than a business decision.
If the phone is an analog only phone, upgrading it will eventually become a necessity as the FCC is eventually going to allow the carriers to turn analog off.
Ron Oakes