Index: opennms-services/src/main/java/org/opennms/netmgt/poller/remote/support/DefaultPollerBackEnd.java
===================================================================
--- opennms-services/src/main/java/org/opennms/netmgt/poller/remote/support/DefaultPollerBackEnd.java	(revision 5226)
+++ opennms-services/src/main/java/org/opennms/netmgt/poller/remote/support/DefaultPollerBackEnd.java	(working copy)
@@ -71,6 +71,7 @@
 import org.opennms.netmgt.poller.remote.PollerConfiguration;
 import org.opennms.netmgt.utils.EventBuilder;
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.orm.ObjectRetrievalFailureException;
 import org.springframework.util.Assert;
 
 /**
@@ -219,8 +220,10 @@
     }
 
     public int registerLocationMonitor(String monitoringLocationId) {
-        
         OnmsMonitoringLocationDefinition def = m_locMonDao.findMonitoringLocationDefinition(monitoringLocationId);
+        if (def == null) {
+            throw new ObjectRetrievalFailureException(OnmsMonitoringLocationDefinition.class, monitoringLocationId, "Location monitor definition with the id '" + monitoringLocationId + "' not found", null);
+        }
         OnmsLocationMonitor mon = new OnmsLocationMonitor();
         mon.setDefinitionName(def.getName());
         mon.setStatus(MonitorStatus.REGISTERED);
@@ -228,8 +231,6 @@
         m_locMonDao.save(mon);
         
         return mon.getId();
-       
-        
     }
     
 
Index: opennms-services/src/main/java/org/opennms/netmgt/poller/remote/PollerFrontEnd.java
===================================================================
--- opennms-services/src/main/java/org/opennms/netmgt/poller/remote/PollerFrontEnd.java	(revision 5226)
+++ opennms-services/src/main/java/org/opennms/netmgt/poller/remote/PollerFrontEnd.java	(working copy)
@@ -10,9 +10,9 @@
 public interface PollerFrontEnd {
     
     public Collection<OnmsMonitoringLocationDefinition> getMonitoringLocations();
-
-	public Collection<PolledService> getPolledServices();
     
+    public Collection<PolledService> getPolledServices();
+    
     /**
      * Is the poller currently registered with the server.
      * @return true if and only if the server has been registered
@@ -38,7 +38,7 @@
      * @param polledServiceId the id of the polledService whose pollTime we are setting
      * @param initialPollTime the time to set its initialPollTime to
      */
-	public void setInitialPollTime(Integer polledServiceId, Date initialPollTime);
+    public void setInitialPollTime(Integer polledServiceId, Date initialPollTime);
     
     /**
      * Poll the service with id polledServiceId and report the results to the server
@@ -73,13 +73,13 @@
      * in the poller configuration
      * @param l
      */
-	public void addConfigurationChangedListener(ConfigurationChangedListener l);
+    public void addConfigurationChangedListener(ConfigurationChangedListener l);
     
     /**
      * Remove a config change listener
      * @param l
      */
-	public void removeConfigurationChangedListener(ConfigurationChangedListener l);
+    public void removeConfigurationChangedListener(ConfigurationChangedListener l);
 
     /**
      * Register a property change listener. (for exampe the 'registered' property)