Important Note about WP-Spamfree

Note about WP-Spamfree - this plugin starts a session for every visitor to your wordpress site, even crawlers. Some crawlers don't like this at all, so I'm excluding them, something along these lines:

if(    (    
stripos($_SERVER['HTTP_USER_AGENT'],"Mozilla") ||    
stripos($_SERVER['HTTP_USER_AGENT'],"Opera") ||    
stripos($_SERVER['HTTP_USER_AGENT'],"Elinks")    )    &&    (    
!stripos($_SERVER['HTTP_USER_AGENT'],"Google") &&    
!stripos($_SERVER['HTTP_USER_AGENT'],"Yahoo") &&    
!stripos($_SERVER['HTTP_USER_AGENT'],"msn")    )){
     session_start();
}