Verifying framed-ip-address using unlang

Hi, Is it possible to use unlang to verify whether framed-ip-address is in the right range or not? We would like to use it on our wholesale proxies. Wholesale customers of ours are allowed to allocate IPs to their customers, but only from certain ranges. Will a normal comparison (> <) work with IP addresses? Or do I have to use one of 'real' languages for that? kind regards Pshem