From OSSEC Wiki

hi to all.

There are a mistake en the postfixt-rules (postfix_rules.xml), we can see :

<rule id="3305" level="5">
   <if_sid>3300</if_sid>
   <id>^504$</id>
   <description>Receipent adrdess must contain FQDN </description>
   <description>(504: Command parameter not implemented).</description>
 </rule>

and of course it's must be address, I thinks.

Pilou