--- a/dwt/widgets/ToolTip.d	Tue Dec 09 21:52:21 2008 +0100
+++ b/dwt/widgets/ToolTip.d	Mon Dec 22 15:10:19 2008 +0100
@@ -31,6 +31,7 @@
 
 import dwt.dwthelper.Runnable;
 import dwt.dwthelper.utils;
+import dwt.graphics.Device;
 import dwt.widgets.Display;
 import dwt.widgets.Event;
 import dwt.widgets.Listener;
@@ -606,7 +607,7 @@
      */
     public void setText (String string) {
         checkWidget ();
-        if (string is null) error (DWT.ERROR_NULL_ARGUMENT);
+        //if (string is null) error (DWT.ERROR_NULL_ARGUMENT);
         if (layoutText !is null) layoutText.dispose ();
         layoutText = null;
         if (boldFont !is null) boldFont.dispose ();
@@ -617,7 +618,7 @@
             layoutText.setText (string);
             Font font = display.getSystemFont ();
             FontData data = font.getFontData () [0];
-            boldFont = new Font (display, data.getName (), data.getHeight (), DWT.BOLD);
+            boldFont = new Font (cast(Device) display, data.getName (), data.getHeight (), DWT.BOLD);
             TextStyle style = new TextStyle (boldFont, null, null);
             layoutText.setStyle (style, 0, string.length ());
         }