does this also appear when you type this special character in any text processor and then fill into FMP with copy/paste?
What is general setting of Win 7 in terms of Language / Region / Date-Format, etc.?
any other characters which misbehave (è, é, à, …)?
Just to rule out a known issue. Is your windows display control panel set to 100% ?
(Those this issue should affect all text, not just special characters.)