CakePHP is truncating a text field, probably encoding related

Here's what I'm trying to do:

I'm parsing incoming email, and using it to create posts in the system. This works almost completely, but there's a few bugs to work out. The one that's currently giving fits is coming up when an email contains certain characters (for example, ® – “ ”), the email body is being truncated at the special character when inserting in to the database. It's happening during the $Model->save() call.

The email is not UTF-8 encoded (and since any user can send email, we can't control the incoming mail encoding), but the database is UTF-8. It seems to work correctly when the email comes in as UTF-8.

Any suggestions? Is there a way to convert the encoding before attempting to save?