This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
To expand on William's answer, it appears that you've configured the host to look for an exploded WAR at TOMCAT_HOME/webapps/app, since TOMCAT_HOME/webapps is the reference point for relative paths (and absolute paths ARE usually recommended). The "explodeWar" attribute would be meaningless since the WAR is expected to be pre-exploded.
An IDE is no substitute for an Intelligent Developer.