DDG/MEL
From the 737 DDG/MEL:
Flight Deck Door (M)May be inoperative provided:
Lock Solenoid a) Door can be locked and
unlocked manually. OR
b) All-cargo operations are
being conducted.
Followed by the (M) Maintenance instructions how to provide the manual lock. So my understanding is, that you can dispatch the a/c only with a flight deck door wich can be locked. (the one or the other way), but without the locking capability -> bad news
yours,