I have a project configured as freestyle Job.

There is the main part of the project (svn://subversion/grails/projekte/LuQ2_Swanenberg_Burg/trunk) and the other Plugins.
The Plugins have to be in a specific SVN revision. So I configured as described in the help the svn urls with "@REVNUMBER".

The job is configured to check hourly the SCM.

The SCM Poll protocoll says that there are changes (higher revision than configured to get) and starts a build (every hour)

Started on 15.06.2016 10:50:00
Received SCM poll call on master for Swanenberg on 15.06.2016 10:50:00
svn://subversion/grails/LuQ2-plugins/aviPlugin/trunk liegt in Revision 142 vor
(Änderungen zu Revision 74)
svn://subversion/grails/LuQ2-plugins/aviSecurityPlugin/trunk liegt in Revision 46 vor
(Änderungen zu Revision 24)
svn://subversion/grails/projekte/LuQ2_Swanenberg_Burg/trunk liegt in Revision 221 vor
svn://subversion/grails/LuQ2-plugins/aviAuditLoggingPlugin/trunk liegt in Revision 16 vor
(Änderungen zu Revision 6)
svn://subversion/grails/LuQ2-plugins/aviJsCssResourcePlugin/trunk liegt in Revision 81 vor
(Änderungen zu Revision 43)
Done. Took 0,13 Sekunden
Changes found

In the console of the job it says no changes found after checkout with correct (configured) revisions:

No changes for svn://subversion/grails/projekte/LuQ2_Swanenberg_Burg/trunk since the previous build
No changes for svn://subversion/grails/LuQ2-plugins/aviAuditLoggingPlugin/trunk since the previous build
No changes for svn://subversion/grails/LuQ2-plugins/aviJsCssResourcePlugin/trunk since the previous build
No changes for svn://subversion/grails/LuQ2-plugins/aviPlugin/trunk since the previous build
No changes for svn://subversion/grails/LuQ2-plugins/aviSecurityPlugin/trunk since the previous build

Expected behaviour would be that only when the revision for the main project (without configured revision number) changed that a build is started.