New property added - "isLookAndFeelDecorated", which indicates if we use the Java look and feel or the system look and feel.

resources/application.properties

@@ -1,4 +1,5 @@
 applicationName=SIP Communicator
 applicationWebSite=http://sip-communicator.org
 fontName=Verdana
-fontSize=12
+fontSize=12
+isLookAndFeelDecorated=false

src/net/java/sip/communicator/impl/gui/UIServiceImpl.java

@@ -792,6 +792,18 @@ private void setDefaultThemePack() {
         SIPCommLookAndFeel lf = new SIPCommLookAndFeel();
         SIPCommLookAndFeel.setCurrentTheme(new SIPCommDefaultTheme());
 
+        // Check the isLookAndFeelDecorated property and set the appropriate
+        // default decoration.
+        boolean isDecorated
+            = new Boolean(ApplicationProperties
+                .getProperty("isLookAndFeelDecorated")).booleanValue();
+
+        if (isDecorated)
+        {
+            JFrame.setDefaultLookAndFeelDecorated(true);
+            JDialog.setDefaultLookAndFeelDecorated(true);
+        }
+
         // we need to set the UIDefaults class loader so that it may access
         // resources packed inside OSGI bundles
         UIManager.put("ClassLoader", getClass().getClassLoader());