Selecting an attribute value from a variable

Hi,

I'm building a variable in xslt like this:

<xsl:variable name="previouspagelastid"
select="concat('@Page',string(@pageNumber - 1),'LastID')"/>

To refer to an attribute in an xml node that I know exists (@Page1LastID for
example).

The root node of my template match looks like this:

<results pageNumber="2" pageCount="3" pageSize="10" resultCount="30"
criteria="" Page1LastID="12"  Page2LastID="" Page3LastID="" Page4LastID=""
Page5LastID="" Page6LastID="">

I'm not sure if its possible but after I declare this variable I want to get
its value, ie. "12"

Any ideas?

Cheers,

Chris