http://maven.apache.org/ref/3.0.2/maven-model/apidocs/org/apache/maven/model/Parent.html#setRelativePath(java.lang.String )
same problems occur as well with maven 2.2.1 as with maven 3.0.x

Found mavenVersion 2.2.1 from file jar:file:/opt/maven/provikmo/lib/maven-2.2.1-uber.jar!/META-INF/maven/org.apache.maven/maven-core/pom.properties
Parsing POMs
ERROR: Processing failed due to a bug in the code. Please report this to jenkins-users@googlegroups.com
java.lang.NullPointerException
at hudson.FilePath.isAbsolute(FilePath.java:224)
at hudson.FilePath.<init>(FilePath.java:212)
at hudson.FilePath.child(FilePath.java:894)
at hudson.maven.MavenModuleSetBuild$RunnerImpl.doRun(MavenModuleSetBuild.java:554)
at hudson.model.AbstractBuild$AbstractRunner.run(AbstractBuild.java:420)
at hudson.model.Run.run(Run.java:1362)
at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:405)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:145)