### Eclipse Workspace Patch 1.0
#P org.eclipse.pde.ui
Index: src/org/eclipse/pde/internal/ui/editor/schema/ElementSection.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.pde.ui/src/org/eclipse/pde/internal/ui/editor/schema/ElementSection.java,v
retrieving revision 1.54
diff -u -r1.54 ElementSection.java
--- src/org/eclipse/pde/internal/ui/editor/schema/ElementSection.java	18 Sep 2007 21:48:53 -0000	1.54
+++ src/org/eclipse/pde/internal/ui/editor/schema/ElementSection.java	2 Oct 2007 23:37:46 -0000
@@ -389,7 +389,10 @@
 
 	private IStructuredSelection handleDelete(Object object, boolean generateSelection) {
 		IStructuredSelection newSelection = null;
-		if (object instanceof ISchemaRootElement) {
+		if (!isEditable()) {
+			Display.getCurrent().beep();
+		}
+		else if (object instanceof ISchemaRootElement) {
 			// Semantic rule: The root "extension" element of a schema
 			// cannot be removed