Added, thanks!
Nice. Thanks, theymos. 
While I've got you, there's a line in Themes/default/languages/Errors.english.php that looks like this:
Code:
$txt['smf31'] = 'This was locked by an administrator. You cannot unlock it.';
Maybe you can change that to one of the following:
Code:
$txt['smf31'] = 'This was locked by a moderator or administrator. You cannot unlock it.';
Code:
$txt['smf31'] = 'This was locked by a moderator. You cannot unlock it.';
(That error message, as it currently stands, gives off the impression that there's something even stronger than a moderator-lock: an administrator-lock. But, I can't find such a thing in 1.1.19.)
@PowerGlove this was probably the fastest patch to be approved and added.
I haven't checked but you're probably right. (I think the quoting-from-locked-threads one was same-day, too.)Time for a moderator to lock this topic, so we know it works 
Haha, yeah. 
I know it's not caused by your patch, but does this mean that a Mod who loses his Mod status after he locked his own topic can't unlock it anymore?
Yup, it does. (Nice catch, BTW.)What it comes down to is that, when locking a topic, SMF first tries to do it on the basis of allowedTo('lock_any') before allowedTo('lock_own'). So, even in cases where the lock could've been recorded in the database as a user-lock (2) rather than a moderator-lock (1), it isn't. I can see what'd need to change logic-wise in LockTopic.php to fix that, but it's a slightly hairy change (it looks deceptively simple, but it's actually kind of tricky to do in a completely clean way), and I don't know that fixing it at this point would be worth it.
Achievement unlocked, inspire PowerGlove 