Not sure if this has been covered, but all of the posts I've seen indicate a fix that does not seem to work for deployed vehicles locking after restart.
I use an sql event to unlock them every hour or 2 (depending on your settings for restarts and what not).
Keep in mind any other sql events that delete unlocked vehicles or deal with vehicles in any way may impact how this works.
Create an event in your sql and add this to run before every restart at the desired time interval.
UPDATE `object_data` SET CharacterID = 0 WHERE CharacterID > 0 AND Classname IN ('M2StaticMG','AGS_INS')
Simply update the 'M2StaticMG','AGS_INS' fields with your desired static weapons or deploy-able items.
This will remove the option to repack the weapon.
Again there may be better solutions out there, but this is working well for me.
If anything can be enhanced or changed to make this more efficient, feel free to chime in. I am an absolute newbie to this sort of stuff.