Irule Error message

Can anyone tell me what might be wrong with my Irule? It seems to be working. I get the message Forbidden when I send a call with the header x-moz set, but I still get this error message in my log.

 

 

 

Error Message:

 

 

Aug 13 12:59:27 tmm tmm[715]: 01220001:3: TCL error: Rule xmoz_irule - can't read "host_pool": no such variable while executing "if { $host_pool ne "" } { pool $host_pool }"

 

 

 

Irule:

 

 

when HTTP_REQUEST {

 

if {[string tolower [HTTP::header x-moz:] ] contains "prefetch" } {

 

HTTP::respond 403 content "Forbidden"}

 

else {set host_pool [findclass [HTTP::host] $::DSHostPoolMap " "] }

 

if { $host_pool ne "" } {

 

pool $host_pool }

 

}