Index: /applications/editors/josm/plugins/CommandLine/src/CommandLine/CommandLine.java
===================================================================
--- /applications/editors/josm/plugins/CommandLine/src/CommandLine/CommandLine.java	(revision 31664)
+++ /applications/editors/josm/plugins/CommandLine/src/CommandLine/CommandLine.java	(revision 31665)
@@ -26,4 +26,5 @@
 import java.awt.BorderLayout;
 import java.awt.Cursor;
+import java.awt.GraphicsEnvironment;
 import java.awt.event.KeyEvent;
 import java.awt.event.MouseEvent;
@@ -253,5 +254,5 @@
 		commands = (new Loader(getPluginDir())).load();
 		if (commands.isEmpty()) {
-			if (JOptionPane.YES_OPTION == JOptionPane.showConfirmDialog(Main.parent,
+			if (!GraphicsEnvironment.isHeadless() && JOptionPane.YES_OPTION == JOptionPane.showConfirmDialog(Main.parent,
 					tr("No command has been found. Would you like to download and install default commands now?"),
 					tr("No command found"), JOptionPane.YES_NO_CANCEL_OPTION)) {
Index: /applications/editors/josm/plugins/cadastre-fr/src/cadastre_fr/CadastrePlugin.java
===================================================================
--- /applications/editors/josm/plugins/cadastre-fr/src/cadastre_fr/CadastrePlugin.java	(revision 31664)
+++ /applications/editors/josm/plugins/cadastre-fr/src/cadastre_fr/CadastrePlugin.java	(revision 31665)
@@ -5,5 +5,4 @@
 import static org.openstreetmap.josm.io.session.SessionReader.registerSessionLayerImporter;
 import static org.openstreetmap.josm.io.session.SessionWriter.registerSessionLayerExporter;
-import static org.openstreetmap.josm.tools.I18n.marktr;
 import static org.openstreetmap.josm.tools.I18n.tr;
 
@@ -283,15 +282,4 @@
         }
         refreshLayersURL();
-
-        /* TODO: remove in july 2012 */
-        if(!Main.pref.getBoolean("cadastregrab.shortcut.warn", false))
-        {
-            Main.pref.put("cadastregrab.shortcut.warn", true);
-            JOptionPane.showMessageDialog(Main.parent,
-                tr("Plugin cadastre-fr used the key shortcut F11 for grabbing,\n"+
-                "which is now allocated for full-screen switch.\n"+
-                "The new grabbing key is F10, but you can change the key\n" +
-                "in the shortcut settings if you want."));
-        }
         refreshMenu();
     }
Index: /applications/editors/josm/plugins/czechaddress/src/org/openstreetmap/josm/plugins/czechaddress/CzechAddressPlugin.java
===================================================================
--- /applications/editors/josm/plugins/czechaddress/src/org/openstreetmap/josm/plugins/czechaddress/CzechAddressPlugin.java	(revision 31664)
+++ /applications/editors/josm/plugins/czechaddress/src/org/openstreetmap/josm/plugins/czechaddress/CzechAddressPlugin.java	(revision 31665)
@@ -4,4 +4,5 @@
 import static org.openstreetmap.josm.tools.I18n.tr;
 
+import java.awt.GraphicsEnvironment;
 import java.awt.event.KeyEvent;
 import java.io.IOException;
@@ -90,5 +91,7 @@
         addStatusListener(this);
 
-        ConflictResolver.getInstance();
+        if (!GraphicsEnvironment.isHeadless()) {
+        	ConflictResolver.getInstance();
+        }
         SelectionMonitor.getInstance();
         Reasoner.getInstance();
Index: /applications/editors/josm/plugins/globalsat/src/org/openstreetmap/josm/plugins/globalsat/GlobalsatPlugin.java
===================================================================
--- /applications/editors/josm/plugins/globalsat/src/org/openstreetmap/josm/plugins/globalsat/GlobalsatPlugin.java	(revision 31664)
+++ /applications/editors/josm/plugins/globalsat/src/org/openstreetmap/josm/plugins/globalsat/GlobalsatPlugin.java	(revision 31665)
@@ -4,4 +4,5 @@
 import gnu.io.CommPortIdentifier;
 
+import java.awt.GraphicsEnvironment;
 import java.awt.event.ActionEvent;
 import java.awt.event.KeyEvent;
@@ -89,11 +90,15 @@
         super(info);
         boolean error = false;
-        try{
+        try {
             CommPortIdentifier.getPortIdentifiers();
-        }catch(java.lang.UnsatisfiedLinkError e){
+        } catch (UnsatisfiedLinkError e) {
             error = true;
-            JOptionPane.showMessageDialog(Main.parent, "<html>" + tr("Cannot load library rxtxSerial. If you need support to install it try Globalsat homepage at http://www.raphael-mack.de/josm-globalsat-gpx-import-plugin/") + "</html>");
+            String msg = tr("Cannot load library rxtxSerial. If you need support to install it try Globalsat homepage at http://www.raphael-mack.de/josm-globalsat-gpx-import-plugin/");
+            Main.error(msg);
+            if (!GraphicsEnvironment.isHeadless()) {
+            	JOptionPane.showMessageDialog(Main.parent, "<html>" + msg + "</html>");
+            }
         }
-        if(!error){
+        if (!error) {
             importAction = new GlobalsatImportAction();
             Main.main.menu.toolsMenu.add(importAction);
Index: /applications/editors/josm/plugins/native-password-manager/src/org/openstreetmap/josm/plugins/npm/NPMPlugin.java
===================================================================
--- /applications/editors/josm/plugins/native-password-manager/src/org/openstreetmap/josm/plugins/npm/NPMPlugin.java	(revision 31664)
+++ /applications/editors/josm/plugins/native-password-manager/src/org/openstreetmap/josm/plugins/npm/NPMPlugin.java	(revision 31665)
@@ -1,4 +1,6 @@
 // License: GPL. For details, see LICENSE file.
 package org.openstreetmap.josm.plugins.npm;
+
+import java.awt.GraphicsEnvironment;
 
 import javax.swing.SwingUtilities;
@@ -26,5 +28,5 @@
                     new NPMCredentialsAgentFactory(sel)
             );
-        } else {
+        } else if (!GraphicsEnvironment.isHeadless()) {
             SwingUtilities.invokeLater(new Runnable() {
                 @Override