Problem fixed. Thank you for all the help.

i wrote an external helper using perl. If any one needs it, feel free to use.
Its pretty crude, but functional.

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external_acl_type ldap_ip %LOGIN %SRC /usr/lib/squid/squid_ldap_ip

acl iplocked external ldap_ip

this is the squid_ldap_ip
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#!/usr/bin/perl
# author : tidalbobo@gmail.com
# use : validate ip from ldap for squid
# GNU GPL
# 2009/09/24
$|=1;

$ldap_server_ip = "__________________";
$ldap_search_base = "______________________"
while(<>) {
chomp;
@vals = split(/ /,$_);
$name=$vals[0];
$ip=$vals[1];

$cmd="ldapsearch -h $ldap_server_ip -x -b O=$ldap_search_base -LLL \"(&(uid=$name)(c=$ip))\" $name";
$returncode = `$cmd`;

if (!$returncode) {
print "ERR\n";
} else {
print "OK\n";
}
}

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