I'm having some problems with Flash Pro CS6, some fonts appear to be rendering correctly only when using classic Textfields but the appear messed up in TLFTextfields. In my case I opened a CS5.5 document in CS6 and all the typography looked wrong.
Can you attach the file or a screenshot ? Also make sure that the font is the same in case if its on a different machine .
More users are encountering this bug: http://forums.adobe.com/message/4495288#4495288