function checkAnrede()
    {
        tmp = document..kdanrede.value;
        filtered = tmp;
        if (tmp.length == 1)
        {
            if (tmp.charAt(0) == 'H' || tmp.charAt(0) == 'h' )
                filtered = 'Herr';
            if (tmp.charAt(0) == 'F' || tmp.charAt(0) == 'f' )
                filtered = 'Frau';
        }
        if (filtered != document..kdanrede.value)
            document..kdanrede.value = filtered;
    }

    function checkPLZ()
    {
        tmp = document..kdplz.value;
        filtered = "";
        for (i=0; i<tmp.length; i++)
        {
            if (tmp.charAt(i) >= '0' && tmp.charAt(i) <= '9')
                filtered = filtered + tmp.charAt(i);
        }
        if (filtered != document..kdplz.value)
            document..kdplz.value = filtered;
    }

    function checkVorwahl()
    {
        tmp = document..kdvorwahl.value
        filtered = "";
        for (i=0; i<tmp.length; i++)
        {
            if (tmp.charAt(i) >= '0' && tmp.charAt(i) <= '9')
                filtered = filtered + tmp.charAt(i);
        }
        if (filtered.length > 0)
        {
        	if (filtered.charAt(0) != '0')
            {
            	filtered = '0' + filtered;
            }
        }
        if (filtered != document..kdvorwahl.value)
            document..kdvorwahl.value = filtered;
    }

    function checkTelefon()
    {
        tmp = document..kdtelefon.value
        filtered = "";
        for (i=0; i<tmp.length; i++)
        {
            if (tmp.charAt(i) >= '0' && tmp.charAt(i) <= '9')
                filtered = filtered + tmp.charAt(i);
        }
        if (filtered.charAt(0) == '0')
        {
            filtered =  filtered.substr(1,filtered.length-1);
        }

        if (filtered != document..kdtelefon.value)
            document..kdtelefon.value = filtered;
    }