letter spacing issue

I've come across a weird issue with an HTML-generated email. I have a headline (Reshuffle for FDIC's Chicago Office) that looks fine in HTML. But when the email client receives it (Outlook XP and Outlook 2007, Mac Mail), a space is appearing between the g and o of Chicago. Viewing the source, the space is apparent but uses no code. It will actually show up if I copy and paste it from the received email:

Reshuffle for FDIC's Chicag o Office

Any idea what's causing it, and if there's any fix to it?

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