Because we have multiple customer, and they want have different mib definition, so we want to make a application that can handle this kind of request. If we use the common mode, we need to create specific code for each of them.
In some ways, I feel this works against what the IANA (Internet Assigned Numbers Authority) envisioned with snmp. Multiple customers wanting their own unique node within the OID is normal. What most people (or organizations) do is register for themselves their own OID number with the IANA under the "enterprises" branch. It's free and I think the form can be found here,
To try some "dynamic" scheme of MIB re-allotment is just asking for trouble - especially if 2 conflicting devices end up on the same network!