% is a wildcard(like * in bash, or Windows explorer) in MySQL when using some operators such as LIKE, it can be escaped and used as a literal % sign by placing a backslash sign in front of it. [CODE]%[/CODE]
I don’t believe this to directly to be the reason, i assume that fog strips out/substitutes the % sign because it may be used in some sort of web based attack on the fog server. Just guessing though.