Cognos Go Dashboard 8.4.1 under WebSphere 6.1

[getrex]

Does anyone have already run Go Dashboard under WebSphere 6.1 ?

I set dashboard.properties file with my default values; I remained all values except the following:
- tomcat_port: 9081  (this is my WAS default port number)
- c8_dispatch: http://myserver:9081/p2pd/servlet/disatch
- c8_gateway: http://myserver:8080/cognos8/cgi-bin/cognos.cgi  --> run OK and I'm working on it.  8080 is my default port under HTTPServer (httpd.conf file)
- c8_webcontent: http://myserver:8080/cognos8

I set the WEB.GATEWAY_URI parameter (Set advanced settings - Configuration) with the value http://myserver:8080/cognos8/cgi-bin/cognos.cgi/gdb/cognos/dashboard/html

Well, in fact I followed all steps of the InfoCenter "Configure IBM Cognos 8 Go! Dashboard to Run on IBM WebSphere Application Server"

My problem is when I click the "New Dashboard" icon in Cognos Connection nothing appears. The message is like if the page does not exist.    "The website cannot display the page - HTTP 500"

Do I have to create a virtual directory or host in httpd.conf file ?
Any suggestions on how to resolve this?