help lines

lines off
lines auto (default)
lines on

The mud supports use of Vt100 escape codes to do line drawing, to make tables look nicer. By default this only happens on terminals that identify themselves as either 'xterm', 'screen', 'linux', 'vt100', 'vt320', or 'cryotel'

If nontheless you want them off, do with "lines off". If you want them on despite what your client claims, do "lines on". "lines auto" is the default and unless you have a problem with it, we recommend keeping it like that.