I just noticed that Nishanth Aravamudan from Canonical made a patch. https://patches.ubuntu.com/libp/libphp-adodb/libphp-adodb_5.20.3-1ubuntu1.patch
I'm not sure having the .pc/ files in there is a good idea. But several changes look good for Debian. Upstream, you migh want the (int) cast on line 121 of drivers/adodb-mysqli.inc.php. Completly removing the mysql and mysqlt drivers seem a bit extreme to me, unless you want to drop php5 support entirely...
