Currently only Outlook is supported. You might be able to write custom code to link to GroupWise.

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Greg Collins [InfoPath MVP]
Please visit: http://www.InfoPathDev.com
Hello Everyone,
Apparently Infopath is setup to send email via Outlook when using the Submit
function. We have GroupWise 6.5 for our messenging system and cannot get the
Submit function to send via GroupWise. Any help on this would be greatly
appreciated.
Thanks in advance.