when doing this:

$sth = ibase_connect ($database, $username, $password)

it ends up with segmentation fault, the script stops to execute and nothing is returned to apache server

On another similar Linux server the connection proceeds but the script gives the same  error message in function $row = ibase_fetch_object ($sth). Insteed the script continues executing and the data are fetched.


On both servers Apache and PHP configurations are equivalent
PHP is compiled with 
./configure --with-apxs=/usr/var/lib/apache/sbin/apxs --with-interbase --without-mysql