There appears to be a problem with gnome-terminal's handling of vt100 graphic line characters. Well, they don't work, at least with either TERM=xterm or TERM=gnome. For an example, run /usr/bin/ctali (gnome-games RPM). When running ctali inside xterm, the main ctali screen contains horizontal and vertical vt100 line graphic characters. The borders of the dices are also drawn using vt100 line graphic characters. When you run ctali inside gnome-terminal, no line graphic characters are shown. The gnome terminfo entry does specify the vt100 line graphic character set capability (the acsc capability), so either the terminfo entry for gnome is wrong, or there's a bug in gnome-terminal.
Which fonts are you using with gnome-terminal? Is it part of the "fixed" set (i.e., "7x14", "10x20")?
No, the font is set to -adobe-courier-medium-r-normal-*-*-140-*-*-m-*-iso8859-1 The only "fixed" point size that is shown in gnome-terminal's preferences is a 12pt font. gnome-terminal's font selection dialog does not appear to offer any other fixed-size 12pt font, except for adobe-courier, which looks OK, actually. I don't see any other fixed point fonts in the font selection dialog.
To clarify -- the sole fixed font size of 12pt is too small.
Adobe courier is an iso8859-1 font. It doesn't have DEC line drawing characters in it.
xterm -fn '-adobe-courier-medium-r-normal--20-140-100-100-m-110-iso8859-1' ctali I still get line drawing characters in xterm, with an adobe font. xterm, apparently, supports VT100 line drawing characters directly, in any font.
I'm forwarding this upstream, and reassigning to the terminal widget in gnome-libs.
xterm emulates line drawing chars for fonts that lack them. upstream as http://bugzilla.gnome.org/show_bug.cgi?id=57443 Closing here.