ndbm support broken?

I can't find a way to configure PHP-4.2.1 so dbmopen() will work on my existing NDBM databases that I've been using with PHP-3.1.18. I'm trying to upgrade from 3.1.18 to 4.2.1 on Solaris 8, and Apache 1.3.26. I started out not using any of the "--with-*db*" options, as they were not needed when I built PHP 3.1.18. But the resulting build generated web pages saying, "Call to undefined function: dbmopen() in blah.php3 on line xxx". On the dbmopen() manual page at http://www.php.net/manual/en/function.dbmopen.php, a user's note says you have to use --with-ndb and --with-db in combination. (This may be a typo for --with-ndbm?) I've tried the following combinations of configure options, with the following results: with-db, with-ndb: with-db, with-ndbm: With either one, it tries to link in libgdbm, the GNU DBM library. with-ndbm: "undefined function: dbmopen()" at runtime. I think something is seriously broken. I searched for "undefined function: dbmopen()" on Google, looking for discussions of this problem, and it came up with hundreds of pages displaying this error, so it looks like a wide-spread problem. What's up? Does anybody understand this? -Allen