I was training a pike Warrior at Beta.
Found my warrior constantly stopped attacking on targets.
For example, when I wanted to hit a monster by putting my mouse on it, my char hit the monster once, then stopped attacking. I switched to manual clicking, still not attacking.
I've tested on normal monsters, football in the town and tt training area, same result.
I back to normal server, use the same pike warrior to test, no such issue at all.
Logged my thief in Beta, using knife to attack targets, no issue at all.
Didn't test on other weapons yet. Guess GM you may be able to figure out what the issue is.