Software :: Cannot Launch Liferay Portal Under Ubuntu?

I had a liferay portal running under windows XP and it worked fine. I decided to migrate system to linux (ubuntu 9.10) and now the portal doesnt launch. Here are my doubts:

* In windows I didnt install tomcat. Launching the /liferay-portal-5.5.2/tomcat-5.5.27/bin/startup.bat it worked fine. Is it mandatory to install tomcat in the linux system in order to work?

* When I launch /liferay-portal-5.5.2/tomcat-5.5.27/bin/startup.sh I didnt get any error, but portal doesnt launch and nothing happens. This are the lines when launching:

Code:

root@wserver:/home/PATH/liferay-portal-5.2.2/tomcat-5.5.27/bin# ./startup.sh
Using CATALINA_BASE: /home/PATH/liferay-portal-5.2.2/tomcat-5.5.27
Using CATALINA_HOME: /home/PATH/liferay-portal-5.2.2/tomcat-5.5.27

[code]....

UPDATE: Reviewing the tomcat logs I saw that apache was running in port 80 and it created a conflict. I have disabled apache on boot and launched again the statup.sh:

org.apache.coyote.http11.Http11BaseProtocol destroy
INFO: Stopping Coyote HTTP/1.1 on http-80
INFO: Failed shutdown of Apache Portable Runtime

using netstat -tul port 80 doesnt appear as used, only ports ipp, postgresql, smtp, 5433, 8005, 5433 and 53585