Yesterday I upgraded via the command-line my test forum from 1.4.3 to 1.4.6 and everything went smoothly. So this morning I did the same thing on my production forum which was on 1.4.4 at the moment of upgrade. However the "forum closed while being upgraded blah" message was still in place after I finished the process. After that I run run-upgrade.php again from the command line but same thing happened. Finally I tried the browser upgrade and it worked.
I think everything is working as expected now (?) but I'd like to know what went wrong. Both production and testing forum have nearly the same number of posts and share the same dedicated server.