330.30(B) says type MC "shall be permitted to be unsupported where the cable:
(2) Is not more than 6 ft. from the last point of support for connections within an accesible ceiling to luminaires or equipment.
Five feet is less than six, last time I looked
Going to a luminaire or other single / dedicated piece of equipment, less than 6 is OK w/o support.
Using it to extend an existing wiring system? support within 12", then every 6' thereafter.
Your AHJ may have (sounds like does have) a different intepretation, but that's the one most of us are familiar with.
BTW, ALL CAPS is SHOUTING...
[This message has been edited by DougW (edited 05-06-2005).]