Here is a current list of handsets Lock-Line will not insure for Cingular,

BMW MOT V60I
ERICSSON P800
ERICSSON P900
HANDSPRING TREO 180
HANDSPRING TREO 270
HANDSPRING TREO 600
HANDSPRING TREO 650
HANDSPRING Visor
MERCEDES MOT STARTAC
MERCEDES MOT TIMEPORT
MERCEDES MOT V60i
MOTOROLA A388
MOTOROLA ACCOMPLI A009
MOTOROLA MPx220
MOTOROLA V3 RAZR
NOKIA 7610
NOKIA NOK9290 Communicator
RIM 6210
RIM 6280
RIM 7280
RIM 7290
SIEMENS SX66
PALM ONE ACE

Hope this helps