function NavigateThrough (event)
{
	if(document.activeElement.form==null)
	{	
		switch (event.keyCode ? event.keyCode : event.which ? event.which : null)
		{
			case 0x25:
				link = document.getElementById ('PrevLink');
				break;
			case 0x27:
				link = document.getElementById ('NextLink');
				break;
		}
		if (link && link.href) document.location = link.href;
	}
	if( event.ctrlKey ==true
	&& event.altKey ==false
	&& event.shiftKey==false
	&& event.metaKey ==false
	&& event.keyCode ==0x0D
	&& document.activeElement!=null
	&& document.activeElement.form!=null)
		document.activeElement.form.submit();
}

document.onkeydown = NavigateThrough;