AC_ARG_WITH([ufdb-db-format],
            [AS_HELP_STRING([--with-ufdb-db-format=FORMAT], [database format; 2.2 or 3.0 (default: 2.2)])],
            [ufdb_db_format=$withval
             if test "$ufdb_db_format" = "2.2"
             then 
                : do nothing
             elif test "$ufdb_db_format" = "3.0"
             then
                CFLAGS="$CFLAGS -DUFDB_DBFORMAT_3=1"
                CXXFLAGS="$CXXFLAGS -DUFDB_DBFORMAT_3=1"
             else
                echo "error: --with-ufdb-db-format must have FORMAT 2.2 or 3.0"
                exit 1
             fi ],
            [ufdb_db_format=2.2] )