As the subject say, we should bring a newer flex in like NetBSD.
Look into my homedir on thud ~mr/newlex.tar.gz
It contains a diff for the old -> new flex or go to /usr/src
and install the lexsrc.tar.
It extracts to lib/libl and usr.bin/lex.
It is obtained from NetBSD.
Try to compile postgres-beta0.03 as BSD44_derived.
the man responsible for such major changes to the cvs repository...
Up-to-date flex is now in -current