Internet mail protocols allow for a message to be sent as multipart/alternate, where one part of the message is plain text and one part is HTML (or any combination of MIME types, actually) and the user-agent (mail client, in this case) will display whatever version it is capable of displaying. I have written a set of custom tags to accomplish this, but I wrote it on company time and do not yet have company approval to post it on the Macromedia Exchange. I would be happy to send the tag to you if you want to provide an e-mail address or provide some other transfer method.
-pcorreia
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