Who is interested in more php extensions? I am currently compiling more extensions for php to use on my router. This is how I am doing it...
Download the php 5.2.6 source
Navigate to <src>/ext/<extension>
phpize
./configure
make
make install
Note that configure may need additional modules
I currently have iconv and gmp already done. iconv is needed for some php scripts and uses the built in iconv implementation however you may need gconv-modules (it gets listed as "unknown") and gmp uses libgmp which is available in ipkg. I have not been able to verify that iconv actually works with the implementation that is present. If you can give me something that I can use to test it then let me know. I'll post both modules up when I get home. They were compiled directly on the router.
EDIT: Well no responses so far so I'll go ahead and attach the two extension that I have done so far. I wanted to do an updated eaccelerator extension but it gets stuck trying to use sysvipc. In 0.9.5.3 they made it so that you have to define a uid (other than zero) that eaccelerator will be running as. Kinda a pain and a brick road.
For each extension simply drop them into /opt/lib/php/extensions and then add the appropriate extension line to /opt/etc/php.ini. I'll do more if there is demand for it but in the meantime I'll do them as needed.
P.S. - gmp is a faster and better library than bcmath. Typically scripts as for either one and recommend gmp if available. The stock php setup include bcmath.