font issue

i am getting scrambled text in my mail client: it looks like Thai script, but it is not...it's just not viewing correctly. It's kinda whacky. If i cut and paste it to another app, the font then shows correctly. But in Mail, it shows all squiggly. Any ideas?

ps- i have also seen this occasional, but not always, on my system update window. It's almost as if it is "spreading" from app to app

just to add to this...if i open some pages (not all) in safari, i get this font issue as well....but if i open the same page in Firefox, there are no problems. Ugh