I created a SmarterTrack ticket via the API, and included Unicode (UTF-8) characters in the message. For example: 👌
The Unicode characters were received into the ticket just fine, and were correctly displayed in the active ticket as well as in the e-mail reply window.
But when the e-mail was received in Outlook, the Unicode characters were changed into two gibberish characters.
I think maybe the problem is that the e-mail is not a complete HTML document -- it's just <p> and <div> elements with no <html>, <head>, <body>, etc. i.e., there is no place to set the <meta charset="utf-8" /> tag.
It seems simple enough to wrap some structure and meta tags around the e-mail content being sent. (If that's what the issue is.)