document.onkeydown = keyhandler;

function keyhandler(e)
{
	if(window.event) // IE
	{
		if ((event.srcElement.type == "textarea") || (event.srcElement.type == "button") || (event.srcElement.type == "reset") || (event.srcElement.type == "submit"));
		else if (window.event.keyCode==13) 
		{	
			window.event.keyCode = 9;
		}
		return true;
	}
	else if(e.which) // Netscape/Firefox/Opera
	{
		if (e.which == 13)
		{
			e.returnValue = false;
			e.cancel = true;
			e.preventDefault(); 
			return false;			
		}	
		return true;
	}
}

/*
function InstalllReturnKeyHandler()
{
	if (document.all) document.onkeydown = function ()
	{
		if ((event.srcElement.type == "textarea") || (event.srcElement.type == "button") || (event.srcElement.type == "reset") || (event.srcElement.type == "submit"))
		{
			return true;
		}
		else
		{
			if (event.keyCode==13) event.keyCode = 9;
			return true;
		}
	}
}

function UnInstalllReturnKeyHandler()
{
	if (document.all) document.onkeydown = function ()
	{
		return true;
	}
}
*/