Here problem is that findbugs depends on dom4j. dom4j itself depends on jaxen, however the jaxen dependency is only marked optinal in the dom4j pom file. to make findbugs work just add <dependency> <groupId>jaxen</groupId> <artifactId>jaxen</artifactId> <version>1.1-beta-6</version> </dependency>
to the file $MAVEN2_REPO/repository/org/codehaus/mojo/findbugs-maven-plugin/1.0- SNAPSHOT/findbugs-maven-plugin-1.0-SNAPSHOT.pom Thanks to Andreas for this :) Aditya Mishra
