Re: problems with xslt on "open" catalog-formats like

I am dealing with a product catalog delivered in the xml-standard ecXML 3.0
from Requisite. From this product catalog i want to create a dynamic
web-navigation with to select our different products with a web-client.
One specific item on that xml-format is, that using that xml-format you can
design your own structure for your catalog. to achieve this, the attributes
for a product are not fix xml-elements, which are declared in a dtd or
schema-file. all "own" attributes are stored in key/value elements to a
product.

You could use a key :-)
 <xsl:key name="items-by-length" match="ITEM"
    use="KEYVALUE[KEY='length']/VALUE"/>

Use as
 <xsl:for-each select="key('items-by-length','100')>
   <xsl:value-of select="KEYVALUE[KEY='price']/VALUE"/>
 </xsl:for-each>

Note that the above will not work on the XML you supplied with
the mail because of the whitespace surrounding all values.

		<KEY>
			Suplier Name
		</KEY>

I hope your original XML is more like
 <KEYVALUE>
  <KEY>Suplier Number</KEY>
  <VALUE>123</VALUE>
 </KEYVALUE>

If not, you'll have to use normalize-space() a lot:
 <xsl:key name="items-by-length" match="ITEM"
   use="normalize-space(KEYVALUE[normalize-space(KEY)='length']/VALUE)"/>
 ...
 <xsl:for-each select="key('items-by-length','100')>
   <xsl:value-of select="normalize-space(KEYVALUE[
    normalize-space(KEY)='price']/VALUE)"/>
 </xsl:for-each>

Note that normalize-space may have the unwanted side effect of
normalizing spaces within keys and values too.