Does System.Web.mail (CDonts) issue smtp quit commands?

Question

.net System.Net.Mail does not issue SMTP quit commands in version 3.5 or lower. Although the problem is fixed in .net v4.0 RTM, unfortunately v4.0 cannot handle attachments in an email larger than 3-4MB's so I can't use it in my solution.

I was thinking of maybe rolling back to the now outdated CDonts found in System.Web.Mail. Can anyone confirm if CDonts mailing routines explicitly issues SMTP Quit commands?