Apache and Tomcat

Hi,

I am a newbie with respect to apache and tomcat. i am a little confuse
after reading the FAQs etc. I have a few questions and I hope you all
can help.

1) I am working on a server running Apache Tomcat 4.1. Can I install
Apache Httpd as my application is usuing php. Can I run it
concurrently? If so, will the domain clash or I have to configure both
to run on different ports?

2) I tried my application on Apache httpd and it runs fine. But the
application does not run properly when I tried using using the method
descibe in
http://blog.taragana.com/index.php/a...mcat-4x-or-5x/

My application has "Pragma:Cache-control:Expires: " on the top of the
webpage and the Tomcat server will shut down after a few clicks. Which
is why I am looking at running both tomcat and apache server
independently.