Commit changes do not trigger builds due to the use of SVN:externals

Our project Apache Directory Trunk here http://opensource.bamboo.atlassian.com/browse/APACHE-DS is not triggered to build when we induce changes on the underlying directories because they are all externals. Meaning we use svn:externals to bring together all the ApacheDS components to build the entire server. Here's what our svn:externals property looks in the directory which is checked out by our project:

apacheds https://svn.apache.org/repos/asf/directory/apacheds/trunk
shared https://svn.apache.org/repos/asf/directory/shared/trunk
daemon https://svn.apache.org/repos/asf/directory/daemon/trunk

Due to this any real work done in these directories does not trigger a build. I suspect to trigger builds properly these externals should be configured for the trigger specification of the project. This way the updated version numbers for these external directories can also be used when determining the criteria to trigger a build.

Thanks!