diff --git a/res/values/colors.xml b/res/values/colors.xml
index 1e3076c..32a2a4b 100644
--- a/res/values/colors.xml
+++ b/res/values/colors.xml
@@ -4,5 +4,6 @@
 	<item name="key_bg" type="color">#282828</item>
 	<item name="key_down_bg" type="color">#1B1B1B</item>
 	<item name="key_label" type="color">#DDDDDD</item>
+	<item name="key_label_locked" type="color">#229933</item>
 	<item name="key_sub_label" type="color">#BDBDBD</item>
 </resources>
diff --git a/srcs/juloo.keyboard2/KeyValue.java b/srcs/juloo.keyboard2/KeyValue.java
index 5994be2..9c25673 100644
--- a/srcs/juloo.keyboard2/KeyValue.java
+++ b/srcs/juloo.keyboard2/KeyValue.java
@@ -10,9 +10,12 @@ class KeyValue
 	public static final int	EVENT_DELETE = -3;
 
 	public static final int FLAG_KEEP_ON = 1;
-	public static final int FLAG_CTRL = (1 << 1);
-	public static final int FLAG_SHIFT = (1 << 2);
-	public static final int FLAG_ALT = (1 << 3);
+	public static final int FLAG_LOCK = (1 << 1);
+	public static final int FLAG_CTRL = (1 << 2);
+	public static final int FLAG_SHIFT = (1 << 3);
+	public static final int FLAG_ALT = (1 << 4);
+	public static final int FLAG_NOCHAR = (1 << 5);
+	public static final int FLAG_LOCKED = (1 << 8);
 
 	private String		_name;
 	private String		_symbol;
@@ -92,9 +95,9 @@ class KeyValue
 		for (int i = 0; i < chars.length(); i++)
 			new KeyValue(chars.substring(i, i + 1));
 
-		new KeyValue("shift", "⇧", '\0', EVENT_NONE, FLAG_KEEP_ON | FLAG_SHIFT);
-		new KeyValue("ctrl", "Ctrl", '\0', EVENT_NONE, FLAG_KEEP_ON | FLAG_CTRL);
-		new KeyValue("alt", "Alt", '\0', EVENT_NONE, FLAG_KEEP_ON | FLAG_ALT);
+		new KeyValue("shift", "⇧", 'S', EVENT_NONE, FLAG_KEEP_ON | FLAG_NOCHAR | FLAG_LOCK | FLAG_SHIFT);
+		new KeyValue("ctrl", "Ctrl", 'C', EVENT_NONE, FLAG_KEEP_ON | FLAG_NOCHAR | FLAG_CTRL);
+		new KeyValue("alt", "Alt", 'A', EVENT_NONE, FLAG_KEEP_ON | FLAG_NOCHAR | FLAG_ALT);
 
 		new KeyValue("backspace", "⌫", EVENT_BACKSPACE);
 		new KeyValue("delete", "⌦", EVENT_DELETE);
diff --git a/srcs/juloo.keyboard2/Keyboard2View.java b/srcs/juloo.keyboard2/Keyboard2View.java
index b44ee16..a692b62 100644
--- a/srcs/juloo.keyboard2/Keyboard2View.java
+++ b/srcs/juloo.keyboard2/Keyboard2View.java
@@ -33,6 +33,7 @@ public class Keyboard2View extends View
 	private Paint			_keyBgPaint = new Paint();
 	private Paint			_keyDownBgPaint = new Paint();
 	private Paint			_keyLabelPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
+	private Paint			_keyLabelLockedPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
 	private Paint			_keySubLabelPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
 
 	public Keyboard2View(Context context, AttributeSet attrs)
@@ -51,6 +52,9 @@ public class Keyboard2View extends View
 		_keyLabelPaint.setColor(getResources().getColor(R.color.key_label));
 		_keyLabelPaint.setTextSize(getResources().getDimension(R.dimen.label_text_size));
 		_keyLabelPaint.setTextAlign(Paint.Align.CENTER);
+		_keyLabelLockedPaint.setColor(getResources().getColor(R.color.key_label_locked));
+		_keyLabelLockedPaint.setTextSize(getResources().getDimension(R.dimen.label_text_size));
+		_keyLabelLockedPaint.setTextAlign(Paint.Align.CENTER);
 		_keySubLabelPaint.setColor(getResources().getColor(R.color.key_sub_label));
 		_keySubLabelPaint.setTextSize(getResources().getDimension(R.dimen.sublabel_text_size));
 		_keySubLabelPaint.setTextAlign(Paint.Align.CENTER);
@@ -141,7 +145,12 @@ public class Keyboard2View extends View
 					KeyDown down = getKeyDown(key);
 					if (down != null)
 					{
-						if (down.pointerId == -1)
+						if ((down.flags & KeyValue.FLAG_LOCK) != 0)
+						{
+							down.flags ^= KeyValue.FLAG_LOCK;
+							down.flags |= KeyValue.FLAG_LOCKED;
+						}
+						else if (down.pointerId == -1)
 							down.pointerId = pointerId;
 					}
 					else
@@ -170,12 +179,12 @@ public class Keyboard2View extends View
 			for (int i = 0; i < _downKeys.size(); i++)
 			{
 				KeyDown downKey = _downKeys.get(i);
-				if (downKey.pointerId == -1)
+				if (downKey.pointerId == -1 && (downKey.flags & KeyValue.FLAG_LOCKED) == 0)
 					_downKeys.remove(i--);
 				else if ((downKey.flags & KeyValue.FLAG_KEEP_ON) != 0)
 					downKey.flags ^= KeyValue.FLAG_KEEP_ON;
 			}
-			if (k.value != null)
+			if (k.value != null && (k.flags & (KeyValue.FLAG_LOCKED | KeyValue.FLAG_NOCHAR)) == 0)
 				_ime.handleKeyUp(k.value, _flags);
 			_downKeys.remove(k);
 			updateFlags();
@@ -218,7 +227,8 @@ public class Keyboard2View extends View
 			for (KeyboardData.Key k : row)
 			{
 				float keyW = _keyWidth * k.width;
-				if (getKeyDown(k) != null)
+				KeyDown keyDown = getKeyDown(k);
+				if (keyDown != null)
 					canvas.drawRect(x + _keyBgPadding, y + _keyBgPadding,
 						x + keyW - _keyBgPadding, y + _keyHeight - _keyBgPadding, _keyDownBgPaint);
 				else
@@ -226,7 +236,9 @@ public class Keyboard2View extends View
 						x + keyW - _keyBgPadding, y + _keyHeight - _keyBgPadding), _keyRound, _keyRound, _keyBgPaint);
 				if (k.key0 != null)
 					canvas.drawText(k.key0.getSymbol(upperCase), keyW / 2 + x,
-						(_keyHeight + _keyLabelPaint.getTextSize()) / 2 + y, _keyLabelPaint);
+						(_keyHeight + _keyLabelPaint.getTextSize()) / 2 + y,
+						(keyDown != null && (keyDown.flags & KeyValue.FLAG_LOCKED) != 0)
+							? _keyLabelLockedPaint : _keyLabelPaint);
 				float textOffsetY = _keySubLabelPaint.getTextSize() / 2;
 				float subPadding = _keyPadding + _keyBgPadding;
 				if (k.key1 != null)