diff --git a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/BuildOptionSettingsUI.java b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/BuildOptionSettingsUI.java
index c99cf7338f6..aae4ae768a8 100644
--- a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/BuildOptionSettingsUI.java
+++ b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/BuildOptionSettingsUI.java
@@ -34,6 +34,8 @@ import org.eclipse.jface.preference.FieldEditor;
 import org.eclipse.jface.preference.FileFieldEditor;
 import org.eclipse.jface.preference.StringFieldEditor;
 import org.eclipse.jface.util.PropertyChangeEvent;
+import org.eclipse.swt.events.ModifyEvent;
+import org.eclipse.swt.events.ModifyListener;
 import org.eclipse.swt.graphics.Point;
 import org.eclipse.swt.widgets.Composite;
 
@@ -104,7 +106,13 @@ public class BuildOptionSettingsUI extends AbstractToolSettingUI {
 								} break;
 		
 								case IOption.BROWSE_NONE: {
-									stringField = new StringFieldEditor(optId, opt.getName(), fieldEditorParent);
+									final StringFieldEditorM local = new StringFieldEditorM(optId, opt.getName(), fieldEditorParent);
+									stringField = local;
+									local.getTextControl().addModifyListener(new ModifyListener() {
+							            public void modifyText(ModifyEvent e) {
+							            	local.valueChanged();
+							            }
+									});
 								} break;
 		
 								default: {
diff --git a/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/StringFieldEditorM.java b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/StringFieldEditorM.java
new file mode 100644
index 00000000000..89cd183f9a2
--- /dev/null
+++ b/build/org.eclipse.cdt.managedbuilder.ui/src/org/eclipse/cdt/managedbuilder/ui/properties/StringFieldEditorM.java
@@ -0,0 +1,36 @@
+/*******************************************************************************
+ * Copyright (c) 2007 Intel Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ * Intel Corporation - Initial API and implementation
+ *******************************************************************************/
+package org.eclipse.cdt.managedbuilder.ui.properties;
+
+import org.eclipse.jface.preference.StringFieldEditor;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.swt.widgets.Text;
+
+/**
+ * This class behaves in the same way as its parent, 
+ * but gives public access to its Text widget, and 
+ * valueChanged() can be called outside.
+ * 
+ * It allows to add extra listeners to Text widget.
+ */
+public class StringFieldEditorM extends StringFieldEditor {
+    public StringFieldEditorM(String name, String labelText, Composite parent) {
+        super(name, labelText, parent);
+    }
+
+    public Text getTextControl() {
+        return super.getTextControl();
+    }
+    
+    public void valueChanged() {
+    	super.valueChanged();
+    }
+}