From the FAA B737 MMEl as
posted on TCCA website : Item 52-8
Flight Deck Door Lock system (Not 14 CFR 25.795 Compliant)
C 1 0 (M) May be inoperative provided:
a) Door lock solenoid is deactivated in locked
position, and
b) Door is verified to lock and unlock manually.
C 1 0 May be inoperative provided supplemental flight deck
door security device is installed and operates
normally.
D 1 0 May be inoperative provided all-cargo operations are
being conducted.
So the only MMEL relief is when something else is there as a lock or there are no pax. Seems sensible enough.
The B777 MMEL on the
same site includes various lock systems which are 25.795 compliant and all have much the same kind of conditions - see the ATA52 section.