[IMGate] is this right in blocking these ips

[brain_damaged-imgate]

Okay read thru the new stuff.  Not that I understood it all.
But we get alot of emails about making the old boy bigger and getting a
diploma from 
these ips  belonging to chinanet.cn.net which turns out to be
61.185.0.0-61.185.255.255
I just want to block the whole thing so
I did in mta_clients_bw the following

61.185.0.0/16   554 ACL mta_clients_bw

then postmapped it.

Right track or wrong one ?

Thanks
MD