1. Make sure your settings.xml contains authentication credentials for the 'jboss-releases-repository' Nexus repo, which is defined in the RHQ root pom. Use the 'jonadmin' user, which is a shared jboss.org account that we use for stuff like this (ask ips for the password):

   <servers>
    ...
    <server>
      <id>jboss-releases-repository</id>
      <!-- jboss.org username and password -->
      <username>jonadmin</username>
      <password>********</password>
    </server>
    ...
   </servers>

2. Publish the release artifacts to the Nexus staging repo:

# Checkout the tag of the release to be published.
git checkout RHQ_x_y_z
# Clean up any target dirs to avoid contamination from previous builds.
git clean -dxf
# Set Maven's max heap to 1 GB, since it hogs a lot of memory when deploying artifacts.
export MAVEN_OPTS="-Xms128M -Xmx1024M -XX:PermSize=64M -XX:MaxPermSize=512M"
# Build and deploy the artifacts for the release. The 'publish' profile causes sources jars to be built for each jar artifact, which JBoss Nexus requires.
mvn -Ddbsetup-do-not-check-schema=true -P publish deploy
# Once this succeeds, remember to re-checkout master or whatever branch you were on before you checked out the tag.

3. If no errors occurred during the above mvn run, go to the Nexus admin console. Log in as 'jonadmin' (same password used for step 1), then click the Staging Repositories link in the left frame. Find the staging repo containing the artifacts you just published; it should be very near the bottom of the table and the name of the repo should contain the string "u:jonadmin". Select the repo and briefly verify that the artifacts look sane. If they do, Close and then Release the repo. If they do not, Drop the repo then repeat steps 2 and 3.

4. Go to http://repository.jboss.org/nexus/content/repositories/releases/org/rhq/rhq-core-domain/ and verify there is an x.y.z subdirectory for the release and that it contains all the correct artifacts. You may need to wait a few minutes for the artifacts to show up.