What steps will reproduce the problem?
1. Load WoW
2. Change Keybind for Reply to Forgotten Chat's reply function (in this case backspace)
3. Have someone whisper you.
4. Hit reply key (backspace)
Note: error only happens once, then does not appear again.

What is the expected output? What do you see instead?
Expect output is that the cursor should jump to the chat box and be able to type in your reply.
Instead, nothing happens. The first time the error appears, but the rest of the time no error but no functioning reply either.

What version of the product are you using?
Release 4.3

Do you have an error log of what happened?
Date: 2009-02-03 16:54:45
ID: 69
Error occured in: Global
Count: 3
Message: [string "BINDING_FC1"] line 1:
   attempt to call global 'FC_OpenLastReply' (a nil value)
Debug:
   [C]: FC_OpenLastReply()
   [string "BINDING_FC1"]:1:
      [string "BINDING_FC1"]:1

Please provide any additional information below.

I have done this with only FC installed, error persists.