well, this one is ending right inside my bag of tricks... incredible! I'd never thought this could be so easy and painless (well, it's perl after all...) with a line like:
xterm -into $xtId -fn $fontname -geometry 150x50+0+0 +sb -bg black -e ./xtermjob.pl &
it doesnt even seem a xterm window, but a widget in its own right.
Thanks!
alessandro