WowAce

What steps will reproduce the problem?
1. Trying to hand in a quest, will give the error sometimes just close the Complete quest window.
2.
3.

What is the expected output? What do you see instead?
Upon clicking to hand in quest, the window closes.

What version of the product are you using?
r243

Do you have an error log of what happened?

BlizzardFrames.lua in bard argument #2 to 'format'.

Please provide any additional information below.
The below line should be where the fault is located.

button:SetText(format("[%d] %s", select(i, ...), button:GetText()))