Server :: Index.php - On Server - Offered For Download Rather Than Being Interpreted?

I have SLES10 SP3 with Apache2 in version 2.2.3 and php5.

I have a virtual host configuration with one vhost.

The /etc/apache2/listen.conf:

Code:

In _web-ims.conf:

Code:

This directory (/etc/apache2/conf.d) also contains the php-config-file php5.conf which now gets interpreted (I suppose):

Code:

Actually things are working OK.

However, ON THE SERVER php only gets interpreted by the FireFox browser when called upon localhost:
[url] //Works fine.

When called thru the IP:

BUT when I call
[url]

FROM ANOTHER CLIENT-COMPUTER, for example my windows computer with XP, using Internet Explorer, then it works!

So, does s.o. have any idea why the same call that does work on another client does not work on the Server? And why does the call with localhost on the server work?

Is that a bug in the FireFox-Browser or where do I have to tell him that he should interpret the php-code also from the IP and not only from loccalhost?