We are trying to setup X.25 over Ethernet (XoE) on SUN using the LLC2
features. The documentation describes it as a straightforward thing.

The trouble begins when LLC2 needs to be initialized (started).
According to manuals/docs, llc2_autoconfig will create configuration
files (in
/etc/llc2/default), and /etc/llc2/llc2_start should then be executed.
However, I always get an error message:

root@xxx> ./llc2_start
Error plumbing /dev/hme: Invalid argument
Error plumbing /dev/hme: Invalid argument
Error plumbing /dev/hme: Invalid argument
Error plumbing /dev/hme: Invalid argument
root@xxx>

llc2_start invokes "llc2_config -P", and if I manually execute that,
result is the same. I have tried just about anything in order to find
out what the problem is, but no luck.