Protect System.Net.Mail.MailMessage.Subject property assaignemnt from throwing an exception

[vmachacek]

When I was downloading around 15000 messages from gmail at one point I got this exception

Unhandled Exception: System.ArgumentException: The specified string is not in the form required for a subject.
   at System.Net.Mail.Message.set_Subject(String value)
   at OpenPop.Mime.Message.ToMailMessage()

Unfortunately, I cannot recreate that error. This is what I found on stack overflow
http://stackoverflow.com/questions/7239733/resolving-the-specified-string-is-not-in-the-form-required-for-a-subject