Hua,
I just now saw your message. About a year ago I did some testing with an ActiveX component called MailBee that does work with IMAP. I was testing SMTP not IMAP so I can't be of much help with that.
They do have a free 39 day trial. For more info see
on this page.
Please send me an email (get my email address from my website), and I will send you some more info.
Regards,
James