I was using a rather old version just fine and upgraded to 2.2.6, but any command results in a stack trace.

The installation went through just fine, but hitting or . results in a stack trace.

arcomm --protocol ssh -u admin s1laba1peg

password for admin:
Enter commands (one per line).
Enter '.' alone to send or 'Crtl-C' to quit.

dir
.
Traceback (most recent call last):
File "/bin/arcomm", line 9, in
load_entry_point('arcomm==2.2.6', 'console_scripts', 'arcomm')()
File "/usr/lib/python2.7/site-packages/arcomm-2.2.6-py2.7.egg/arcomm/entry.py", line 130, in main
line = input('> ')
File "", line 1
.
^
SyntaxError: unexpected EOF while parsing

Also just running the arcomm command with no parameters also results in a stack trace. It should probably just display command help:

arcomm

Traceback (most recent call last):
File "/bin/arcomm", line 9, in
load_entry_point('arcomm==2.2.6', 'console_scripts', 'arcomm')()
File "/usr/lib/python2.7/site-packages/arcomm-2.2.6-py2.7.egg/arcomm/entry.py", line 78, in main
raise ValueError('no endpoints')
ValueError: no endpoints