It's an encoding problem his end, or decoding your end - I think, for the apostrophe sign.
See RSS Google and "'" Problem
and Google '
"It makes some of your emails hard to understand."
Mention to him that this is a common problem and direct him to the site above or to Google ' to show him what you mean. It would be interesting for you both to track down the problem...and a work-around solution.
That's interesting! Note what happens when I merely try to copy and past those symbols from your post into this post: this website reproduces them as Google ' It's converted them back to AN APOSTROPHE!