[imp] Is IMP secure?

pradit@tubtim.cri.or.th pradit@tubtim.cri.or.th
Thu, 25 Apr 2002 17:31:38 +0700 

I had got error
(Fatal error: Undefined class 
name 'log'in /usr/local/apache/htdocs/webmail/horde/lib/Horde.php on line 155) 

after login

help me