TAGS file for gzipped source in emacs/xemacs

[mwooding@thecity.sfsu.edu (Miguel Wooding SF Ten.Union)]

Does anyone know how to make and use a TAGS file when the source files
are gzipped? I installed the xemacs20-supportel package, which
installs all of the *.el elisp files in gzipped form.  (I would guess
that emacs[19,20]-el also install the sources in gzipped form.) I
suppose I could simply unzip them, but I'd rather not use all the
extra space, and then any upgrade wouldn't work properly since dpkg
would only overwrite the gzipped files. I like to have the option of
looking at the source when I'm trying to understand what a command
does; plus it helps me understand elisp better.  I'm not, however,
planning to modify the source right now.
 
It seems that this might be a two step problem: (1) Generate the TAGS 
file, using etags, from the gzipped sources, and (2) Make {x}emacs 
auto-decompress the sources.  I don't really know a good easy 
solution.  
 
If anyone has any ideas, I'd appreciate it.   
 
Thanks, 
--Miguel