xsl match first letter of data?

Using MSXMLDOM with XML file:

<windows>
	<product>
		<name>Product Name</name>
		....
	</product>
</windows>

and XSL:

<?xml version="1.0" encoding="ISO-8859-1"?>

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

<xsl:template match="windows">

    <xsl:for-each select="product">
	<xsl:sort select="Name"/>
	<xsl:if test="Category='business'">
      <div class="menuitem">
        <a href="{URL}"><xsl:value-of select="Name"/></a>
      </div>
      <div class="catdesc">
        <xsl:value-of select="Description"/> [<a href="{URL}">More</a>]
      </div>
	</xsl:if>  		
    </xsl:for-each>
</xsl:template>
</xsl:stylesheet>

Question:

What xsl:if or other tag can I use to specify that only 'products' with a 'name' beginning with the letter "a" should be displayed?  Hope this makes sense, I am 
fairly new to XSL but I have read for two days now and can't find a way to do this so far. Thanks!



 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list