The good thing about the HTML email proc that I created is that it uses the tcllib mime library so there's lots of flexibility there.
The bad thing about the HTML email proc that I created is that it uses the tcllib mime library and AOLserver doesn't play nicely with tcl packages and these libraries. Since you're using it, you probably have seen that it source
s base64.tcl, mime.tcl, and smtp.tcl each time the proc is called. There's gotta be a better way.
Off the top of my head, I don't recall the issues that AOLserver has with tcllib and packages, but at the time that I wrote that code I researched here and on the AOLserver list archives and ended up with this solution. I would not recommend this if you're going to be pushing out a large volume of email.