OK so that's indicating that a Javascript function can't be found - which is going to be a function that's in a file in your browser cache (something in a .js file).
Since it's not hurting anything (i.e. the error itself is the annoyance, nothing useful is broken) try turning off script warnings in IE - see "Method 1" in this article:
http://support.microsoft.com/kb/308260
Since it's not hurting anything (i.e. the error itself is the annoyance, nothing useful is broken) try turning off script warnings in IE - see "Method 1" in this article:
http://support.microsoft.com/kb/308260