[exim] Problem with router / socket

Hi all,
This is my custom router that check user quota:

maildir_overquota:
driver = redirect
domains = +local_domains
condition = ${if eq {${readsocket{/var/run/exim_sockd.sock}{QUOTACHECK
${lookup ldap {LDAP_Q_HOMEDIRECTORY} {$value} fail} ${lookup ldap
{LDAP_Q_QUOTA} {$value} fail} $message_size}{3s}{\n}{0}}}{0}{0}{1}}
allow_fail
data = :fail: Mailbox quota exceeded

Now I have change my external socket daemon for check user quota from
file socket (/var/run/exim_sockd.sock) to "port socket (that listen on
127.0.0.1 port 9221)
How to change in my router for use new socket?

I have try with:
condition = ${if eq {${readsocket{127.0.0.1 9221}{QUOTACHECK ${lookup
ldap {LDAP_Q_HOMEDIRECTORY} {$value} fail} ${lookup ldap {LDAP_Q_QUOTA}
{$value} fail} $message_size}{3s}{\n}{0}}}{0}{0}{1}}

but don't work :-)

Can you help me?
Thanks

Marco