[RBASE-L] - RMail embedded attachment types

[Doug Hamilton]

Hi All -
I'm trying to embed a simple text document into an email using R:Mail 
9.5 with the EMBED_ATTACHMENT command.
The example in R:Mail documentation is:
PLUGIN RMail 'v1|EMBED_ATTACHMENT Holiday07.gif#image/gif'
The format according to the documentation is:
format: YourFilename.EXT#ContentType

The example embeds a gif file but I can't find what ContentType to use 
for text.

Is there documentation somewhere of the various ContentTypes?

TIA
Doug