OK. I've delved deep into this problem. The malformed OID seems to be caused by SNMP::_main_loop in SNMP.pm. However there is no _main_loop subroutine.

AUTOLOAD, I thought. And yes there is an AUTOLOAD sub, but it has nothing to do with _main_loop.

In the debugger there is a sub called _main_loop. But stepping over it just seems to skip it like a 'n'. Please, anyone, any ideas on how I could see what is going on within this sub?

I haven't read the perldoc on the debugger, yet. That's where I'm going now.

!unlike

"The price if ignorance, which is of course that you must learn from those who know." Socrates (paraphrased)