I've been told that there are numerous connections left open on the server. I found an explanation (pasted below) at http://www.squirrelmail.org/wiki/NewIMAPConnections. It does state that SM makes lots of connections but also states that these are closed. Is there something that could happen to cause these or a lot of these connections to remain open? Is this still the way current versions of SquirrelMail operate?
"SquirrelMail makes a new IMAP connection with every folder and mail operation. That means, with each click, the IMAP server gets another user logged in, a tiny itty bitty request is made, then the IMAP session is shut down.
Because we can not open persistent connections with PHP for each user on your system. We tried pconnect, but we could only make it open one connection, not one connection per user (perhaps you can see a BIG difference like we did).
As a result, sometimes your IMAP server doesn't let us log in, due to the number of ConnectionsPerMinute.
We are thinking of making an IMAP gateway to hopefully speed things up, but that is still in planning.
If you can figure out a nice way to make PHP create a new persistent connection with PHP, we'd love to hear it. Until then, we are stuck with the immense overhead involved with nearly every IMAP mail server for each click."
I am currently using SquirrelMail 1.2.2.