I spent some time tonight installing the newest version of squirremail. I tell you, this is one hell of a great application. I use squirrelmail as my primary method to access my personal email. The application has all of the functionality that you could need. A very cool feature of the application is
that it has an extensible architecture so developers add all kinds of cool add-on features.
If anyone out there is looking for ann add-on PHP webmail application, I highly recommend that you check out Squirrelmail.