XML duplicates using Javascirpt need help!!

[wallyson]

ok Here is a snippet of my xml file:

<Holidays>
        <Data>
            <Month>August</Month>
            <Day>2</Day>
            <Holiday>Virgin of the Angels Day</Holiday>
            <Country>(CR)</Country>
            <Year>2006</Year>
        </Data>
        <Data>
            <Month>August</Month>
            <Day>3</Day>
            <Holiday>Fast Tishaa Beav</Holiday>
            <Country>(ISR)</Country>
            <Year>2006</Year>
        </Data>
                                <Data>
            <Month>August</Month>
            <Day>3</Day>
            <Holiday>Fast Tishaa Beav</Holiday>
            <Country>(ISR)</Country>
            <Year>2006</Year>
        </Data>
                                 <Data>
            <Month>August</Month>
            <Day>3</Day>
            <Holiday>Fast Tishaa Beav</Holiday>
            <Country>(ISR)</Country>
            <Year>2006</Year>
        </Data>
</Holidays>

as you can see its simply an xml file full of holidays,days,country,month, and year.

A user selects a month from a drop down list (such as august) and then all teh holidays in that month should appear. Ok now the challenge, I do not want the duplicate holidays to print out.

Im using an xpath way to do it, like this:

nodes = xmlDoc.selectNodes("xpath expression here");

How do I NOT print out the duplicate holidays?