function onkeypress(evt)
{
	if(!evt) var evt = window.event;
	if(evt.keyCode) code = evt.keyCode;
	else if (evt.which) code = evt.which;

	if(evt.ctrlKey)
	{
		var tag = (evt.target || evt.srcElement).tagName;
		if(tag != "INPUT" && tag!= "TEXTAREA")
		{
			var H;
			if(code == 37)
			{
				H = document.getElementById("prev_link");
			}
			if(code == 39)
			{
				H = document.getElementById("next_link");
			}
			
			if(H)
			{
				location.href = H.href;
			}
		}
	}
}
document.onkeydown = onkeypress;