Call to undefined function mysqli_connect()

[sdfv sdfv]

Hi,

I installed php 5 with IIS 5.0 in isapi mode.
In php.ini, i took extension php_mysql.dll
I set the directory-extension to c:\php\ext.
I copied libmysql.dll in ext directory.

Now mysql_connetc works, but not mysqli_connect. I get
"Call to undefined function mysqli_connect()".

In php.ini, there is no way to select php_mysqli.dll (doesn't exist). That file exist in dir ext. So why that error? I read all the documentation of the php-site, but couldn't find an answer.

thanks for helping.
maisql