What module is xfce4-session in?

[Theo. Sean Schulze]

Hello,

Everytime I start up xfce4, I get a message telling me that 
xfce4-session cannot be found.  (I am using Xfce4 on a Slackware 9.1 
system that I regularly upgrade to current using swaret.  My current 
version of Xfce4 is 4.0.2.)  I have downloaded the source package that 
contains the tar'd and bzip'd module packages, but none of them is 
called xfce4-session.  So, I am assuming that xfce4-session is included 
as part of another module.  Can someone tell me which one it is in?

TIA,

Sean