I was in a openACS bug fixing mood. So here's my fix:
at the top or bboard/admin-community-view.tcl in a page validation section you'll find the line:
set n_positions [validate_integer "N Postings" n_postings]
should be
set n_positions [validate_integer "N Postings" $n_postings]
(note the dollar sign)
but that's not all!...:) because once you get past that there's another...
replace all instances of $QQstart_date with $start_date
Then it works.