Linking to older extension libraries

I'm trying to upgrade from PHP 4.0.1 to anything 4.0.2+ on a Cobalt Qube 3. I'm doing this to enable CURL support, which didn't arrive until 4.0.2. The problem is, that there are two libraries, i18n and cce, on the Cobalt Qube 3, which exist only in a binary form .so. Now, when I try and upgrade PHP and link back to those modules, I get a module API version error: Warning: i18n: Unable to initialize module Module compiled with debug=0, thread-safety=0 module API=20000609 PHP compiled with debug=0, thread-safety=0 module API=20001214 These options need to match in /usr/sausalito/ui/web/info.php on line 5 Is there any way of linking to an older API, maybe a wrapper library? Alternately, would it be a big job to put CURL support into v4.0.1, based on the 4.0.2 source? Thanks, Sam