/var/db/sup/refuse works for me ...
Code:
% cat /var/db/sup/refuse
ports/arabic
ports/chinese
ports/french
ports/german
ports/hebrew
ports/hungarian
ports/japanese
ports/korean
ports/polish
ports/portuguese
ports/russian
ports/ukrainian
ports/vietnamese
ports/palm
Note that cvsup/csup will *not* remove these directories, so if you already have a previous snapshot, you will have to manually delete these directories (i.e. rm -rf `cat refuse | xargs`).