Monitoring Optical Network and devices from Nortel

We have a pretty large Optical Network that we use to transport video and high speed data. We are using Nortel's Optical Metro 6500, 6110, 5200 and 3500s. We tried enabling the snmp services on one of the OM 6500s and was able to add to Solarwinds V8.5.1;but it did not support the Interfaces MIB to poll the interface status/information. Most of the posts here seem to be related to cisco products. As NPM is capable of Nortel devices we would like to know how this can be proceeded. One option that we heard is that we need TL1 interpreter for Solarwinds. Do you support TL1 interpreter? I tried searching for any relevant posts here and didn't have luck finding them. 

thanks,

Om