Hi!
Pop2owa should use the same config as internet explorer.
If not works try to execute proxycfg -u
See http://msdn.microsoft.com/en-us/library/ms761351%28VS.85%29.aspx
If your proxy use a expecific user and password try to config config.xml file (proxy tag)
2009-08-19 20:53:39 UTC in POP3/SMTP to OWA