Old thread I know, but in case anyone else is still looking for the answer, I found the distribution zip (with bootstrap) in the maven repo here:

https://repository.jboss.org/nexus/content/groups/public/org/jboss/embedded/jboss-embedded/beta3.SP12/jboss-embedded-beta3.SP12-bin.zip

Looks like this in the pom:

<dependency>

                              <groupId>org.jboss.embedded</groupId>

                              <artifactId>jboss-embedded</artifactId>

                              <version>${jboss.embedded.version}</version>

                              <classifier>bin</classifier>

                              <type>zip</type>

                              <scope>test</scope>

</dependency>

I don't think there is an official maven artifact containing just the bootstrap.