function validate_required(field,alerttxt)
{
	with (field)
	{
		if (value==null||value=="")
		{alert(alerttxt);return false}
		else {return true}
	}
}

function validate_email(field,alerttxt)
{
	with (field)
	{
		apos=value.indexOf("@")
		dotpos=value.lastIndexOf(".")
		if (apos<1||dotpos-apos<2) 
  			{alert(alerttxt);return false}
		else {return true}
	}
}

function validate_emailform(thisform)
{
	with (thisform)
	{
		if (validate_required(e,"Vyplňte Váš email !")==false)
  			{e.focus();return false}

		if (validate_email(e,"Váš email není korektní !")==false)
  			{e.focus();return false}

	}
	thisform.submit();
}