Server: Every server. This is a client issue across all servers official and private.
Description: There are several bugs and glitches involved with a weapon’s attacks and animations. They range from; Your character not having an attack animation, having an animation but not doing damage, to incorrectly displaying which weapon you have equipped in your hand. Several of these bugs are exploitative and they need to be addressed asap. A mod or dev can personally pm me and I can describe how and what these bugs are and how to exploit them.
Workarounds: Most weapon glitches are fixed by unequipping and re-eqiupping the weapon. You may need to relog or die in order to fix the animation glitches. In one case, your character actually needs to die.