Dear Hans,

There is something wrong in this example, but I'm not able to figure
out if it's a problem in my code or a bug (with MKII it works just
fine).

When compiled with MKIV, I get extra space on the right, as if a
column on the right was missing.

\def\mymacro#1#2#3{\VL #1 \NC #2 \NC #3 \VL\AR}
\starttable[|cp(2em)|rp(2em)|rp(2em)|]
\HL
\VL 1 \NC 2 \NC 3 \VL\AR
\mymacro123
\HL
\stoptable

Mojca

PS: \startTEXpage ... \stopTEXpage around the code behaves as if table
was infinitely small. Is that OK?