My girlfriend's bard has been unplayable for some time now due to this. I've even had her remake the character two different times. All three versions wind up the same; it gets to where she can't log in. Then, when she can, she crashes whole zones when she does =P She just started playing a warrior instead, heh.
Had a thread going here about this same issue, including some of the op_code errors I was seeing. However, just seems something that has to be dealt with. Admittedly, I've seen it become a lot rarer lately than in past versions.