I've just released version 0.3.12 of TwistedSNMP, I didn't call it 0.4 mostly because the PySNMP-v4 code isn't yet usable (the PySNMP-v4 engine is just too slow to be useful in our applications). The changes to the version that uses v3.5+ are those mentioned earlier this week that reduce the latency during integration of large data-sets into a table retriever.