GWT (event.getCharCode) behaves differently in IE and Firefox

I was going through the tutorial available on GWT website for StockWatcher application and testing the application as described in Step4: Manage Events on the Client.

Below piece of code behaves differently in Firefox and IE7. In IE7 this works well, i.e. If I enter some junk characters in Text field and h开发者_高级运维it Enter "event.getCharCode() == KeyCodes.KEY_ENTER" line gets executed successfully and I could see an alert message. However this same line does not work, if I use Firefox.

When I use Firefox and press Enter, event.getCharCode returns some junk character. What am I doing wrong here? or is this expected behavior?

newSymbolTextBox.addKeyPressHandler(new KeyPressHandler() {
          public void onKeyPress(KeyPressEvent event) {
            if (event.getCharCode() == KeyCodes.KEY_ENTER) {
              addStock();
            }
          }
        });

Use a KeyUpHandler instead of a KeyPressHandler to catch non-character keys (like enter, escape, etc.). Call KeyUpEvent#getNativeKeyCode() to get the key code.