Try using the AscW() function. This will return the character code of the character you pass it. (If you're just using the plain ASCII character set you can use Asc(). AscW() is for Unicode.)
First, figure out the character code of the characteryou're looking for by selecting the character and calling a function like:
msgbox "code = " & AscW(Selection.Characters(1).Text)
Then, use that code in your condition:
iCharCode = 40 ' (or whatever your code was)
For Each ch in Selection.Characters
If AscW(ch) = iCharCode then Msgbox "It's here"
Next
Hope this helps.