Logging URL redirection

I need to log the requests to some URLs that are redirected to another domain. I need to know if there's still clients trying to access the OLD domain. I wrote an aFLEX to do this, and it works ok in my lab enviroment. I did the same configuration at the production network, but it doesn't work. There's not traffic matching the rule. I did a debug at the ADC (axdebug) and there's nothing matching the aFlex.

Here's the aFlex:

#Log HTTP request to Redirected web sites
when HTTP_REQUEST {

if {([CLASS::match [string tolower [HTTP::host]] starts_with cl-logging-redirections])} {
#set slogging yes
set cs_ip_method_uri "[IP::client_addr] [HTTP::method] [HTTP::uri]"
set site_web [HTTP::host]
set date_time_request [clock format [TIME::clock seconds] -format {%Y-%m-%d %H:%M:%S} ]
set cs_user_agent [string map {" " "+"} [HTTP::header "User-Agent"]]
set c_request_version [HTTP::version]
if {[HTTP::header exists Referer]} {
set cs_referer [HTTP::header "Referer"]
} else { set cs_referer "-" }
set redirection [HTTP::header Location]
set log_str "log-redirection-$site_web $date_time_request $cs_ip_method_uri $cs_referer $cs_user_agent HTTP/$c_request_version $redirection"
log local0.INFO $log_str
}
}

I need some help to find where's the error.