Can not erase the File Input Text in Firefox 3

[GoogleCodeExporter]

This is the simple test code

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.gwtext.client.widgets.Viewport;
import com.gwtext.client.widgets.form.FormPanel;
import com.gwtext.client.widgets.form.TextField;

public class HelloWorld implements EntryPoint
{

    public void onModuleLoad()
    {   
        final FormPanel formPanel = new FormPanel();
        formPanel.setFrame(true);
        formPanel.setWidth(700);
        formPanel.setLabelWidth(200);
        formPanel.setFileUpload(true);
        formPanel.setUrl(GWT.getModuleBaseURL() + "test");

        TextField tf=new TextField("file", "file");
        tf.setInputType("file");
        formPanel.add(tf);
        Viewport viewport = new Viewport(formPanel);
    }

}
In the FireFox 3 browser mode, when I click the text box (not the Browse
button), a File selection Dialog pops up. I could not erase the text
already in the box.   When I click the text box in IE, no file selection
Dialog pops up, and I can use "Backspace" to delete the text in box.

This means I have no option to select no file once I select file once in FF3. 

-jason

Original issue reported on code.google.com by jasonzha...@gmail.com on 13 Sep 2008 at 4:01