custom login form with validation

Hi
I am wanting to add a custom login form to a page template.
If the user is not logged in then the form is displayed. If the user is logged in then some other content is shown. I have this bit nailed.
However the login form is tricky…..
I have seen on several posts that I should be using the wp_login_form( $args );
Which is fine, however when I click login without filling anything in.. or don’t fill a field in correctly… I am redirected to wp-login, where an error is displayed.
I want these form validation errors to display on the homepage where the form resides.
How can I achieve this?

Any help would be much appreciated.