diff --git a/maven-core/src/main/java/org/apache/maven/DefaultMaven.java b/maven-core/src/main/java/org/apache/maven/DefaultMaven.java
index 41fddfbab8..40fbe1c2db 100644
--- a/maven-core/src/main/java/org/apache/maven/DefaultMaven.java
+++ b/maven-core/src/main/java/org/apache/maven/DefaultMaven.java
@@ -153,6 +153,7 @@ public class DefaultMaven
 
         ProfileManager globalProfileManager = request.getGlobalProfileManager();
 
+        boolean foundProjects = true;
         try
         {
             loadSettingsProfiles( globalProfileManager, request.getSettings() );
@@ -169,6 +170,8 @@ public class DefaultMaven
             {
                 MavenProject superProject = projectBuilder.buildStandaloneSuperProject( request.getLocalRepository() );
                 projects.add( superProject );
+                
+                foundProjects = false;
             }
 
             rm = new ReactorManager( projects );
@@ -204,6 +207,8 @@ public class DefaultMaven
         try
         {
             MavenSession session = createSession( request, rm );
+            
+            session.setUsingPOMsFromFilesystem( foundProjects );
 
             try
             {
diff --git a/maven-core/src/main/java/org/apache/maven/execution/MavenSession.java b/maven-core/src/main/java/org/apache/maven/execution/MavenSession.java
index eb17b6fce3..1c230cbcd0 100644
--- a/maven-core/src/main/java/org/apache/maven/execution/MavenSession.java
+++ b/maven-core/src/main/java/org/apache/maven/execution/MavenSession.java
@@ -46,6 +46,8 @@ public class MavenSession
 
     private final String executionRootDir;
 
+    private boolean usingPOMsFromFilesystem;
+
     public MavenSession( PlexusContainer container, Settings settings, ArtifactRepository localRepository,
                          EventDispatcher eventDispatcher, ReactorManager rpm, List goals, String executionRootDir )
     {
@@ -126,4 +128,14 @@ public class MavenSession
     {
         return executionRootDir;
     }
+
+    public void setUsingPOMsFromFilesystem( boolean usingPOMsFromFilesystem )
+    {
+        this.usingPOMsFromFilesystem = usingPOMsFromFilesystem;
+    }
+    
+    public boolean isUsingPOMsFromFilesystem()
+    {
+        return usingPOMsFromFilesystem;
+    }
 }
\ No newline at end of file
diff --git a/maven-core/src/main/java/org/apache/maven/plugin/DefaultPluginManager.java b/maven-core/src/main/java/org/apache/maven/plugin/DefaultPluginManager.java
index 37f5036aca..15b6f8d83f 100644
--- a/maven-core/src/main/java/org/apache/maven/plugin/DefaultPluginManager.java
+++ b/maven-core/src/main/java/org/apache/maven/plugin/DefaultPluginManager.java
@@ -310,6 +310,19 @@ public class DefaultPluginManager
         throws ArtifactResolutionException, PluginManagerException, MojoExecutionException
     {
         MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();
+        
+        // NOTE: I'm putting these checks in here, since this is the central point of access for 
+        // anything that wants to execute a mojo.
+        if( mojoDescriptor.isProjectRequired() && !session.isUsingPOMsFromFilesystem() )
+        {
+            throw new MojoExecutionException( "Cannot execute mojo: " + mojoDescriptor.getGoal() + ". It requires a project, but the build is not using one." ); 
+        }
+        
+        if ( mojoDescriptor.isOnlineRequired() && session.getSettings().isOffline() )
+        {
+            // TODO: Should we error out, or simply warn and skip??
+            throw new MojoExecutionException( "Mojo: " + mojoDescriptor.getGoal() + " requires online mode for execution. Maven is currently offline." );
+        }
 
         if ( mojoDescriptor.isDependencyResolutionRequired() != null )
         {