XML for breakfast?

With the XML below I’m trying to go through whichever “Item” I want and access it’s “itemImage’s”.

I’m trying to do it like this at the moment which is… well… not the right syntax.

trace(rootGlobal.xml.Item.mainImages[2].itemImage.text()[3])

I want to specify which portfolio item and the item image… so output i’d want for the example above is “images/portfolioImage2-3.jpg”

   
<portfolioItems>
      <Item>
        <id>1</id>
        <ItemColour>1</ItemColour>
        <orientation>P</orientation>
        <itemTitle>Test Item</itemTitle>
        <itemPreviewImage>previewImages/previewImage1.jpg</itemPreviewImage>
        <mainImages>
            <itemImage>images/portfolioImage1-1.jpg</itemImage>
            <itemImage>images/portfolioImage1-2.jpg</itemImage>
            <itemImage>images/portfolioImage1-3.jpg</itemImage>
            <itemImage>images/portfolioImage1-4.jpg</itemImage>
            <itemImage>images/portfolioImage1-5.jpg</itemImage>
        </mainImages>
        <itemDescription>In this image there is some ***s.</itemDescription>
    </Item>
    <Item>
        <id>2</id>
        <ItemColour>1</ItemColour>
        <orientation>P</orientation>
        <itemTitle>Test Item</itemTitle>
        <itemPreviewImage>previewImages/previewImage2.jpg</itemPreviewImage>
        <mainImages>
            <itemImage>images/portfolioImage2-1.jpg</itemImage>
            <itemImage>images/portfolioImage2-2.jpg</itemImage>
            <itemImage>images/portfolioImage2-3.jpg</itemImage>
            <itemImage>images/portfolioImage2-4.jpg</itemImage>
            <itemImage>images/portfolioImage2-5.jpg</itemImage>
        </mainImages>
        <itemDescription>In this image there is some mechanised geese. Look at them hop.</itemDescription>
    </Item>
</portfolioItems>

Hope there are some XML fiends out there,
any help would be great.
Thanks