Hi,I have the same problem with a personalized XML for SNMP requests on IP Phones.I haven't reply on my questions too, so i think there isn't a lot of people using SNMP :/There is 2 howto/wiki but they are not very precise:
http://wiki.ocsinventory-ng.org/index.php?title=Documentation:SNMPxml/fr
https://wiki.ocsinventory-ng.org/index.php?title=Documentation:SNMP/fr