dba.so and dba_open()

I got Call to undefined function: dba_open() .

To use dba_open() on linux Apache machine. I need to have the dba.so, right?

But I have searched all the files on my linux server, there is no dba.so.

Is that dba.so coming with the regualr php installation?

How can I get dba.so installed if it is not in my original php?

Thanks.

correct me if i am wrong. dba.so is not included in the regualr php package. i have to install the dba.so by myself?

I have new php4.3 installed.

But I don't have dba.so?

My question:

1) Could I run configure command differently so I can have dba.so? If so, how?

2) Or should I have to install dba package in addition to my php4.3? If so, where can I find that dba package for php4.3 and how to install it?

I tried to install dba.so package for php4.2.3 on my php 4.3, it is not working. it requires some components that come with php4.2.3?