diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/ProjectLanguageMappingWidget.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/ProjectLanguageMappingWidget.java
index 0009a08f7f9..15f9d490019 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/ProjectLanguageMappingWidget.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/ProjectLanguageMappingWidget.java
@@ -100,6 +100,7 @@ public class ProjectLanguageMappingWidget extends LanguageMappingWidget {
 		buttons.setLayoutData(new GridData(SWT.BEGINNING, SWT.BEGINNING, false, false));
 
 		Button addButton = new Button(buttons, SWT.PUSH);
+		addButton.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false));
 		addButton.setText(PreferencesMessages.ProjectLanguagesPropertyPage_addMappingButton);
 		addButton.addListener(SWT.Selection, new Listener() {
 			public void handleEvent(Event event) {
@@ -133,6 +134,7 @@ public class ProjectLanguageMappingWidget extends LanguageMappingWidget {
 		});
 
 		Button removeButton = new Button(buttons, SWT.PUSH);
+		removeButton.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false));
 		removeButton.setText(PreferencesMessages.ProjectLanguagesPropertyPage_removeMappingButton);
 		removeButton.addListener(SWT.Selection, new Listener() {
 
diff --git a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/WorkspaceLanguageMappingWidget.java b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/WorkspaceLanguageMappingWidget.java
index 514bccba29b..9d9e24bede1 100644
--- a/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/WorkspaceLanguageMappingWidget.java
+++ b/core/org.eclipse.cdt.ui/src/org/eclipse/cdt/internal/ui/language/WorkspaceLanguageMappingWidget.java
@@ -79,6 +79,7 @@ public class WorkspaceLanguageMappingWidget extends LanguageMappingWidget {
 			buttons.setLayoutData(new GridData(SWT.BEGINNING, SWT.BEGINNING, false, false));
 	
 			Button addButton = new Button(buttons, SWT.PUSH);
+			addButton.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false));
 			addButton.setText(PreferencesMessages.ProjectLanguagesPropertyPage_addMappingButton);
 			addButton.addListener(SWT.Selection, new Listener() {
 				public void handleEvent(Event event) {
@@ -98,6 +99,7 @@ public class WorkspaceLanguageMappingWidget extends LanguageMappingWidget {
 			});
 	
 			Button removeButton = new Button(buttons, SWT.PUSH);
+			removeButton.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false));
 			removeButton.setText(PreferencesMessages.ProjectLanguagesPropertyPage_removeMappingButton);
 			removeButton.addListener(SWT.Selection, new Listener() {