diff --git a/example-attach/pom.xml b/example-attach/pom.xml
index 7b85229..3b911dc 100644
--- a/example-attach/pom.xml
+++ b/example-attach/pom.xml
@@ -28,6 +28,7 @@
           </execution>
           <execution>
             <id>attach-artifact-signatures</id>
+            <phase>none</phase>
             <goals>
               <goal>attachsignatures</goal>
             </goals>
diff --git a/plugin/src/main/java/org/neo4j/build/plugins/ease/AttachSignaturesMojo.java b/plugin/src/main/java/org/neo4j/build/plugins/ease/AttachSignaturesMojo.java
index f78187f..0a4cbbf 100644
--- a/plugin/src/main/java/org/neo4j/build/plugins/ease/AttachSignaturesMojo.java
+++ b/plugin/src/main/java/org/neo4j/build/plugins/ease/AttachSignaturesMojo.java
@@ -20,8 +20,9 @@
 
 import java.io.File;
 import java.util.ArrayList;
-import java.util.Iterator;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 import org.apache.maven.artifact.Artifact;
 import org.apache.maven.artifact.factory.ArtifactFactory;
@@ -31,8 +32,8 @@
 import org.codehaus.plexus.util.FileUtils;
 
 /**
- * Attaches all unattached signatures of signed artifacts in the build directory
- * with the project.
+ * Attaches all signatures of signed artifacts to the project. Will fail on
+ * missing signatures.
  * 
  * @goal attachsignatures
  * @requiresProject true
@@ -48,13 +49,6 @@ public class AttachSignaturesMojo extends AbstractMojo
      */
     private MavenProject project;
 
-    /**
-     * @parameter default-value="${project.attachedArtifacts}
-     * @required
-     * @readonly
-     */
-    private List attachedArtifacts;
-
     /**
      * Used to create artifact instances.
      * 
@@ -64,40 +58,71 @@ public class AttachSignaturesMojo extends AbstractMojo
      */
     protected ArtifactFactory artifactFactory;
 
+    private final Set<String> attachedIds = new HashSet<String>();
+
     @Override
     public void execute() throws MojoExecutionException
     {
-        List<Artifact> artifacts = new ArrayList<Artifact>();
-        for ( Iterator i = attachedArtifacts.iterator(); i.hasNext(); )
-        {
-            Artifact artifact = (Artifact) i.next();
-            artifacts.add( artifact );
-        }
-        // simply attach the signature of all non-signature artifacts
+        List<Artifact> artifacts = new ArrayList<Artifact>(
+                project.getAttachedArtifacts() );
+        project.getAttachedArtifacts()
+                .clear();
         for ( Artifact artifact : artifacts )
         {
             String type = artifact.getType();
-            if ( !type.endsWith( ".asc" ) )
+            if ( artifact.getArtifactId()
+                    .equals( project.getArtifactId() ) && artifact.getGroupId()
+                    .equals( project.getGroupId() ) )
             {
-                File artifactFile = artifact.getFile();
-                String signaturePath = artifactFile.getAbsolutePath() + ".asc";
-                File signatureFile = FileUtils.getFile( signaturePath );
-                if ( signatureFile.exists() )
+                // only add back the project artifacts we want
+                if ( type.equals( "pom.asc" ) || type.equals( "pom" ) )
                 {
-                    String classifier = null;
-                    if ( artifact.hasClassifier() )
+                    attach( artifact );
+                }
+            }
+            else
+            {
+                // re-attach and check if there's a signature to attach as well
+                attach( artifact );
+                if ( !type.endsWith( ".asc" ) )
+                {
+                    File artifactFile = artifact.getFile();
+                    String signaturePath = artifactFile.getAbsolutePath()
+                                           + ".asc";
+                    File signatureFile = FileUtils.getFile( signaturePath );
+                    if ( signatureFile.exists() )
                     {
-                        classifier = artifact.getClassifier();
+                        String classifier = null;
+                        if ( artifact.hasClassifier() )
+                        {
+                            classifier = artifact.getClassifier();
+                        }
+                        Artifact signatureArtifact = artifactFactory.createArtifactWithClassifier(
+                                artifact.getGroupId(),
+                                artifact.getArtifactId(),
+                                artifact.getVersion(), type + ".asc",
+                                classifier );
+                        signatureArtifact.setFile( signatureFile );
+                        attach( signatureArtifact );
+                    }
+                    else
+                    {
+                        throw new MojoExecutionException(
+                                "Missing signature for artifact: " + artifact );
                     }
-                    Artifact signatureArtifact = artifactFactory.createArtifactWithClassifier(
-                            artifact.getGroupId(), artifact.getArtifactId(),
-                            artifact.getVersion(), type + ".asc", classifier );
-                    signatureArtifact.setFile( signatureFile );
-                    project.addAttachedArtifact( signatureArtifact );
-                    getLog().info(
-                            "Attached signature: " + signatureArtifact.getId() );
                 }
             }
         }
     }
+
+    private void attach( Artifact artifact )
+    {
+        String id = artifact.getId();
+        if ( !attachedIds.contains( id ) )
+        {
+            project.addAttachedArtifact( artifact );
+            attachedIds.add( id );
+            getLog().info( "Attached: " + id );
+        }
+    }
 }