Hi There,
I've used IMAP to design a custom vacation auto-responder for Gmail. My code is so standard that you can use it with any other provider with few modifications.
Check my solution here...
http://www.codeproject.com/KB/IP/IAMONVAC.aspx
If you like it, please vote for it as Best VB.Net article here...
http://www.codeproject.com/script/Surveys/VoteForm.aspx?srvid=926
Please note that you need to be logged in to codeproject.com to vote.Thank you.
BR,
Khallaf