[xsl] Difficult Grouping/Matching problem

["Kenny Akridge" <kenny@xxxxxxxxxxxxxxxxx>]

I am trying to list out a number of columns with event dates in a header and
then place an 'X' in the cell that corresponds to the date for attendees of
the events.  
The XML is like this:

<ArrayOfAttendance xmlns:xsd="http://www.w3.org/2001/XMLSchema";
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";>
  <Attendance>
    <FirstName>John</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-10T00:00:00.0000000-05:00</ClassDate>
    <Attend>YES</Attend>
  </Attendance>
  <Attendance>
    <FirstName>John</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-17T00:00:00.0000000-05:00</ClassDate>
    <Attend>NO</Attend>
  </Attendance>
  <Attendance>
    <FirstName>John</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-20T00:00:00.0000000-05:00</ClassDate>
    <Attend>YES</Attend>
  </Attendance>
  <Attendance>
    <FirstName>John</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-24T00:00:00.0000000-05:00</ClassDate>
    <Attend>YES</Attend>
  </Attendance>
  <Attendance>
    <FirstName>Jane</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-10T00:00:00.0000000-05:00</ClassDate>
    <Attend>YES</Attend>
  </Attendance>
  <Attendance>
    <FirstName>Jane</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-17T00:00:00.0000000-05:00</ClassDate>
    <Attend>YES</Attend>
  </Attendance>
  <Attendance>
    <FirstName>Jane</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-20T00:00:00.0000000-05:00</ClassDate>
    <Attend>NO</Attend>
  </Attendance>
  <Attendance>
    <FirstName>Jane</FirstName>
    <LastName>Doe</LastName>
    <ClassDate>2004-01-24T00:00:00.0000000-05:00</ClassDate>
    <Attend>YES</Attend>
  </Attendance>
</ArrayOfAttendance>

I want to produce HTML output like this:

Name		1/10/04	1/17/04
-------------------------------
John Doe	  X		  
Jane Doe	  X		  X

Name		1/20/04	1/24/04
-------------------------------
John Doe	  X		  X
Jane Doe			  X

This is assuming that I can only fit n number of dates on one line for a
printed report.

I am having a difficult time approaching this and I am tempted to give up
using XSL to handle this.

Any thoughts would help.  Thanks.