Does Tomcat is loaded? If not, check your Java configuration.
Otherwise use this script for starting your Tomcat server,
tomcat_start.sh
Code:
echo ""
echo "=== APACHE TOMCAT ==="
export JAVA_HOME=/usr/java/jdk1.5.0_05/jre
apache-tomcat-5.5.28/bin/startup.sh
sleep 5
echo "=== DONE! ==="
echo ""
You must "cd" in the /usr/local/ folder of your linux server before starting this script.
Take care about your java version. Im my case i'm using jdk1.5.0_05.
The java version provided on the documantation page of pwAdmin project is jdk1.5.0_21 (if i remember exactly)