blocking :feature-not-implemented

Hi

I need help with blocking communication. I'm using ejabberd 1.1.2 as internal part of our company server. I need to set some configuration to block communication among groups in shared roster. I was trying mod_filter, but when i allow it in ejabberd.cfg (even without acl and access configuration), the services in discovery don't load at all. I was trying may way, but still nothing. So...was looking for other solution. Found privacy rules, but when i query

iq from='admin@testjb.com' to='testjb.com' type='get' id='disco1'>
query xmlns='http://jabber.org/protocol/disco#info'/>
/iq

i don't receive ...feature var='urn:xmpp:blocking'/..., it's not implemented.
Module mod_privacy is enable.

Can someone help me, i have no idea what i'm doing wrong.
Thanks.

Ps.You can also contact me on GG(3315767).Thanks