The Maven team is pleased to announce the Multi-project plugin 1.0 release!

http://maven.apache.org/reference/plugins/multiproject/

The Maven Multi-project plugin is a plugin that helps with building multiple related projects.

Changes in this version:
o Removed clean from multiproject:site
o update to velocity 1.4-dev
o Change from ${basedir}/multiproject/navigation.xml to ${maven.docs.src}/navigation.xml
  as the nav source for user supplied nav templates
o Bad j:set tags fixed
o Made aggregation directory configurable, use artifactId instead of
  name for creating site directories / URLs.
o Updated multiproject:site to automate navigation generation for all projects
o Added multiproject 'install', 'install-snapshot', 'deploy' and 'deploy-snapshot'
  facility
o Rename plugin from reactor to multiproject to reduce confusion

You can download the Multi-project plugin here:
http://www.ibiblio.org/maven/maven/plugins/maven-multiproject-plugin-1.0.jar

Have fun!
dIon