Just FYI, php was upgraded to version 5 last night.... only causalty is the webmail which gives an error message when you send email.... however, the mail is still sent. I'll fix this tonight.
Update: Upgraded squirrelmail and it looks like that fixed things. Let me know anyone if you have issues.
I could have told ya that.
At work we use squirrelmail and did the PHP4->5 upgrade... same issue, except at that point squirrelmail hadn't fixed it for PHP5 yet.
A few days of working with them later, fixed up and updated squirrelmail.