Well I think there's a way to send HTML e-mails manually:
https://vborg.vbsupport.ru/showthread.php?t=172026
https://vborg.vbsupport.ru/showthread.php?t=137537
https://vborg.vbsupport.ru/showthread.php?t=137593
https://vborg.vbsupport.ru/showthread.php?t=187790
But as far as converting the standard e-mails, you could always try editing the vbphrase that matches the mail - throw in some HTML code and see if it works.