Summarising XML datasets

Hi,

I have a problem formatting some XML I am receiving from a 3rd party
application that I cannot alter.

The application is querying a database that has a table called photo and a
table called photosubject, there is a one to many relationship between photo
and photosubject.

As a simple example, photo 1 is of a house and it has been deemed to cover
subjects X, Y and Z.  When I submit some arguments to the application I am
getting an XML document in this format:

<results>
  <photograph>
   <id>1</id>
   <name>House</name>
   <description>House 1</description>
   <subject>X</subject>
  </photograph>
  <photograph>
   <id>1</id>
   <name>House</name>
   <description>House 1</description>
   <subject>Y</subject>
  </photograph>
  <photograph>
   <id>1</id>
   <name>House</name>
   <description>House 1</description>
   <subject>Z</subject>
  </photograph>
</results>

What I want to do if possible is to render the information using xslt as:

HouseID  |  House  |  Description | Subjects
===========================================
1        |  House  |  House 1     | X, Y, Z

Any ideas?

Cheers,

Chris