function inputWithSample(field, sample_text) {
    field.parents('form').submit(function(){
        if (field.hasClass('sample')) {
            field.val('');
        }
    });
    
    function setSample(field) {
        if (field.val() === "") {
            field.addClass('sample');
            field.val(sample_text);
        }
    }

    setSample(field);
    
    field.keyup(function(){
        if (field.val() !== sample_text) {
            field.removeClass('sample');
        }
    });
    field.click(function(){
        if (field.hasClass('sample') && field.val() == sample_text) {
            field.removeClass('sample');
            field.val('');
        }
    });
    field.blur(function(){
        setSample(field);
    });            
}