Installing Piwik on Ubuntu 10.04

I have MYSQL and PHP5 running along with Wordpress.
I downloaded latest.zip, unzipped it in /www/piwik/, created the required MYSQL database and attempted to run http//mydomain.xxx/piwik

I get the error screen:
Piwik couldn’t write to some directories

Directories:
/tmp//templates_c
/tmp//cache
/tmp//assets
/tmp//tcodf

Have not been created. I created all these directories and I got the same error.

What am I doing wrong?
AG

with your FTP chmod 777 these directories?

Thank you very much - problem solved, it works!
AG