how to use external modules of php3?

[ChangWoo Park <soph@doit.ajou.ac.kr>]

My linux is potato.

I have installed php3, module for postgresql.
(php3.07, Postgresql6.4.2 - using dselect)
I cannot use pg_pconnect, others function..
I don't know solution Error message that unsupported or undefined function.
Option is turn on in /etc/php3/cgi/php3.ini, /etc/php3/apache/pnp3.ini

I have tested in msql, but I have got same result.

if you know, send me solution.

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up to now, I wish to test php3.

I will use informix in my project.
In this case, what to do?
I wasn't able to find Debian package for informix.
it is possible without external package that like postgresql, db, dbase or
mysql

if possible, send me two solution that informix and msql or postgresql.

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e-mail; soph@doit.ajou.ac.kr
homepage: doit.ajou.ac.kr/~soph