Quest Accept dialog oddity

[rlp122]

I have ISBoxer set up and working beautifully. I have three WoW accounts that I am boxing on one computer. Everything works great except on one of the accounts I get this odd black dialog after I auto accept quests from the main character. See below. Any ideas of what I may have set on this character to cause this?

[lax]

Appears to be from one of your Addons, and no I don't know which one but it's not from ISBoxer