1) make sure you have enabled "Show Calendar from Forum Summary?" or something like that in Calendar Settings (CP), if it doesn't work re-modify ubb_forum_summary.cgi and public_forum_summary.pl from calendar instructions...
2) try the following:
open ubb_calendar_ssi.cgi
find:
code:
replace with:
code:
[qb] print "document.write(unescape('".UBBCGI::escape($calendarRow)."'));";
BTW, the 6.4 version of calendar hack already does something like that
