<build>
<plugins>
<plugin>
<groupId>org.codehaus.cargo</groupId>
<artifactId>cargo-maven2-plugin</artifactId>
<configuration>
<container>
<containerId>tomcat5x</containerId>
<type>remote</type>
</container>
<configuration>
<type>runtime</type>
<properties>
<cargo.tomcat.manager.url>http://localhost:8080/manager/html</cargo.tomcat.manager.url>
<cargo.remote.username>admin</cargo.remote.username>
<cargo.remote.password>admin</cargo.remote.password>
</properties>
<deployables>
<deployable>
<groupId>groupId</groupId>
<artifactId>artifactId</artifactId>
<type>war</type>
</deployable>
</deployables>
</configuration>
</configuration>
</plugin>
</plugins>
</build>

–> check your %TOMAT_HOME%/conf/tomcat-users.xml for tomcat manager user name and password