[xsl] Where have I gone wrong?

["Mark Wilson" <drmark@xxxxxxxxxxxxxxx>]

I am embarressed to ask (blush):
I am building a library catalog for my club. I put each book and an XML 
sequence like (but simplified)
<List>
   <Entry>
       <Subject>Some Subjects</Subject>
       <Title>Some Title</Title>
   </Entry>
   .......
</List>
I then did a grouping using XSLT 2.0's new element (Thank you XSLT 
designers) so that I get a list of all the subjects, but only a singel entry 
for each. Now I want to create:
<List>
   <Subject>First Subject
       <Title> First title associated with this subject</Title>
       <Title> Next title associated with this subject</Title>
   </Subject>
   .....
</List>
More to the point, I want to collect all of the sibling nodes from an entry 
with all of the sibling nodes from other entries that share the same 
subject. I have really looked and just failed to understand what I am 
looking at.
Thanks,
I can give you the actual stylesheet I wrote if that would help. Although I 
can output the expected single copy of each subject element in order, I 
cannot seem to organize the associated sibling nodes to make a subject 
catalog of the books with all the titles associated with a subject collected 
under that subject.
Mark