DOCBOOK-APPS: Sorting order in glossaries

Title: Sorting order in glossaries

When printing my docbook glossary with the DSSSL style sheets, I get the glossary terms just in the order as they occur in XML. Is there any way to get an alphabetically sorted glossary list ? 

It is tricky to preserve the sorting order by hand (if you have many glossary terms or documents in different language versions). 

Thanks for any input.

Matthias