diff --git a/modules/tasks/swraid.nix b/modules/tasks/swraid.nix
index c51664d7e32..a662f06c215 100644
--- a/modules/tasks/swraid.nix
+++ b/modules/tasks/swraid.nix
@@ -15,7 +15,7 @@ let
     echo "$@" >> ${logFile}
     case $1 in
       (NewArray)
-        initctl emit -n new-devices
+        initctl emit -n new-raid-array
         ;;
       (*) ;;
     esac
@@ -25,33 +25,51 @@ in
   
 {
 
-  jobs.swraid =
-    { startOn = [ "startup" "new-devices" ];
-      
-      script =
-        ''
-          # Load the necessary RAID personalities.
-          # !!! hm, doesn't the kernel load these automatically?
-          for mod in raid0 raid1 raid5; do
-              ${modprobe}/sbin/modprobe $mod || true
-          done
-      
-          # Scan /proc/partitions for RAID devices.
-          ${mdadm}/sbin/mdadm --examine --brief --scan -c partitions > ${tempConf}
-          
-          if ! test -s ${tempConf}; then exit 0; fi
-      
-          # Activate each device found.
-          ${mdadm}/sbin/mdadm --assemble -c ${tempConf} --scan
-        '';
+  jobs.swraid = {
+    startOn = [ "new-raid-array" ];
+    description = "Assemble RAID arrays.";
 
-      task = true;
-    };
+    script = ''
+      # Load the necessary RAID personalities.
+      # !!! hm, doesn't the kernel load these automatically?
+      for mod in raid0 raid1 raid5; do
+        ${modprobe}/sbin/modprobe $mod || true
+      done
+
+      # Save previous probe
+      mv ${tempConf} ${tempConf}.old
+
+      # Scan /proc/partitions for RAID devices.
+      ${mdadm}/sbin/mdadm --examine --brief --scan -c partitions > ${tempConf}
+
+      if ! diff ${tempConf} ${tempConf}.old > /dev/null; then
+        # Activate each device found.
+        ${mdadm}/sbin/mdadm --assemble -c ${tempConf} --scan
+
+        # Send notifications.
+        initctl emit -n new-devices
+      fi
+
+      # Remove previous configuration.
+      rm ${tempConf}.old
+    '';
+
+    task = true;
+  };
 
   jobs.swraidEvents = {
     name = "swraid-events";
     description = "Watch mdadm events.";
     startOn = [ "startup" ];
+
+    postStart = ''
+      echo > ${tempConf}
+
+      # Assemble early raid devices.
+      initctl emit -n new-raid-array
+    '';
+
+    # !!! Someone should ensure that this is indeed doing what the manual says.
     exec = "${mdadm}/sbin/mdadm --monitor --scan --program ${mdadmEventHandler}";
   };