Download and install Tomcat 5.5.17 into your preferred directory. From now on, the directory where you installed Tomcat will be referred to as $TOMCAT_HOME.

Download and install JDK 5 . Set an environment variable called %JAVA_HOME% to point to your JDK directory.

Note: If you are using JDK 1.4, you must download and install the JDK 1.4 Compatability Package at tomcat.apache. For JDK 1.4 users: delete $TOMCAT_HOME/webapps/ROOT/WEB-INF/lib/xercesImpl.jar. For JDK 5 users: move $TOMCAT_HOME/webapps/ROOT/WEB-INF/lib/xercesImpl.jar to TOMCAT_HOME/common/endorsed.

Download MySQL from www.mysql.com and install.

Create and edit $TOMCAT_HOME/conf/Catalina/localhost/ROOT.xml to set up the portal web application.

<Context path="">
</Context>

Download liferay-portal-pro-4.x.war.

Download portlet.jar and portal-kernel.jar from liferay Portal 4.x Dependencies.

Edit $TOMCAT_HOME/conf/catalina.properties.

common.loader=
    ${catalina.home}/common/classes,\
    ...\
    ${catalina.home}/common/lib/ext/*.jar

Configure data sources for your database. Make sure the JDBC driver for your database is accessible by Tomcat.

Edit $TOMCAT_HOME/conf/Catalina/localhost/ROOT.xml.

<Context...>
    <Resource
        name="jdbc/LiferayPool"
        auth="Container"
        type="javax.sql.DataSource"
        driverClassName="com.mysql.jdbc.Driver"
        url="jdbc:mysql://localhost/lportal?useUnicode=true&amp;characterEncoding=UTF-8"
        username=""
        password=""
        maxActive="100"
        maxIdle="30"
        maxWait="10000"
    />
</Context>

Populate your database with the portal schema and default data.

Create a mail session bound to mail/MailSession.

Edit $TOMCAT_HOME/conf/Catalina/localhost/ROOT.xml and configure a mail session.

<Context...>
	<Resource
		name="mail/MailSession"
		auth="Container"
		type="javax.mail.Session"
		mail.transport.protocol="smtp"
		mail.smtp.host="localhost"
	/>
</Context>

Configure JAAS.

Edit $TOMCAT_HOME/conf/Catalina/localhost/ROOT.xml and configure a security realm.

<Context...>
	<Realm 
		className="org.apache.catalina.realm.JAASRealm"
		appName="PortalRealm"
		userClassNames="com.liferay.portal.security.jaas.PortalPrincipal"
		roleClassNames="com.liferay.portal.security.jaas.PortalRole"
		debug="99"
		useContextClassLoader="false"
	/>
</Context>

Repeat this step for a file called $TOMCAT_HOME/conf/Catalina/localhost/tunnel.xml if you want to enable Liferay's HTTP tunneling.

Create $TOMCAT_HOME/conf/jaas.config.

PortalRealm {
	com.liferay.portal.kernel.security.jaas.PortalLoginModule required;
};

Edit $TOMCAT_HOME/bin/catalina.bat so that Tomcat can reference the login module.

rem ----- Execute...

set JAVA_OPTS=-Xms128m -Xmx512m -Dfile.encoding=UTF8 -Duser.timezone=GMT -Djava.security.auth.login.config=%CATALINA_HOME%/conf/jaas.config

Delete contents $TOMCAT_HOME/webapps/ROOT directory.

Unpack liferay-portal-pro-4.x.war to $TOMCAT_HOME/webapps/ROOT.

For supporting UTF-8 UIRIEncoding, edit $TOMCAT_HOME/conf/server.xml.

<!-- Define a non-SSL HTTP/1.1 Connector on port 8080 -->
   <Connector port="8080" maxHttpHeaderSize="8192"
               maxThreads="150" minSpareThreads="25" maxSpareThreads="75"
               enableLookups="false" redirectPort="8443" acceptCount="100"
               connectionTimeout="20000" disableUploadTimeout="true"
               URIEncoding="UTF-8"
   />

Run Tomcat, point browser to http://localhost:8080. Sign in as test@liferay.com and password test