While the function probably works exactly the way you would expect, the code analyzer for CF9 doesn't produce an error (or even an "information") flag if you have a function in your code named "trace".
You can even create the function and the server won't throw an error like it's supposed to when it encounters this:
Instead it will compile fine and then when you try to use the function you may or may not get an error message like "Attribute validation error for TRACE. The value of the VAR attribute is invalid. Cannot set variable with name [blah blah]".
This is about the 3rd or 4th time I've discovered unexpected and mostly undocumented changes in behavior in CF9 or 9.0.1. Does anyone else feel like the release of this version of CF was a bit sloppy or is it just me?