Form Processing Script: Results In HTML Mail Format?

I have purchased a form processing script, which basically saves the data into a database, emails certain people's email addresses with the form results, and also sends an email to the user that filled in the form with a thank you email.

However, all the emails are being sent in plain text format. I would like to change this to HTML so I can make the results look nicer and also make the thank you email look nicer.

I have emailed the script developers, but have yet had a response from them, so i thought id put a post on here!

I have found the part of the coding that sends the Thank You email out to the user once they have filled in the form:

'/// Send Autoresponse
if replyto<>"" and (autoresponse<>"" or sendcopy<>"") then
if sendcopy<>"" then autoresponse=autoresponse & vbcrlf & vbcrlf & message
call sendmail(replyto,mailadmin,formname,autoresponse)
end if
end if .......