To generate a JBPM project, use the following maven command
mvn archetype:generate -DarchetypeGroupId=net.labidi -DarchetypeArtifactId=jbpm-archetype -DarchetypeVersion=1.0.0 -DarchetypeRepository=http://maven.khaled-labidi.net/repo -DgroupId=myCompany -DartifactId=myJBPMProject -DpackageName=com.mycompany.jbpm -Dversion=1-SNAPSHOT
And here's a sample output
[INFO] Scanning for projects...
[INFO] Searching repository for plugin with prefix: 'archetype'.
[INFO] ------------------------------------------------------------------------
[INFO] Building Maven Default Project
[INFO] task-segment: [archetype:generate] (aggregator-style)
[INFO] ------------------------------------------------------------------------
[INFO] Preparing archetype:generate
[INFO] No goals needed for project - skipping
[INFO] Setting property: classpath.resource.loader.class => 'org.codehaus.plexus.velocity.ContextClassLoaderResourceLoader'.
[INFO] Setting property: velocimacro.messages.on => 'false'.
[INFO] Setting property: resource.loader => 'classpath'.
[INFO] Setting property: resource.manager.logwhenfound => 'false'.
[INFO] [archetype:generate]
[INFO] Generating project in Batch mode
[INFO] Archetype defined by properties
Downloading: http://maven.khaled-labidi.net/repo/net/labidi/jbpm-archetype/1.0.0/jbpm-archetype-1.0.0.jar
18K downloaded
18K downloaded
18K downloaded
18K downloaded
18K downloaded
18K downloaded
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESSFUL
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 5 seconds
[INFO] Finished at: Fri Oct 03 14:11:22 AFT 2008
[INFO] Final Memory: 8M/14M
[INFO] ------------------------------------------------------------------------