Format Bug List?

[Max <max0r () DIGITALSAMURAI ORG>]

I'm currently throwing together a little utility that searches a file for
a list of functions and then compares that functions arguments to a couple of rules.
Namely, that there are no quotation marks or %'s. I realize this is a far cry from being accurate, but its easier than 
manually reading through thousands of lines of code. In any event, I was curious if anyone has put together a list of 
the standard library functions that are particularly vulnerable to format bugs?


-Max