[horde] session_start is throwing an error

[Mike Poznecki]

Hi all,  I have a new Horde install.  When I try to log in, I get HORDE: PHP ERROR: session_start(): open(/var/lib/php/session/sess_5skahi3sno28lsa, 0_RDWR) failed: No such file or directory (2) [PID 3821 on line 204 of "/usr/share/pear/Horde/Session.php"]
Why would I be getting this error?