GNU Tar --listed-incremental is backing up dir structure every time

[Jason Donald]

Hi,

1) I am using GNU tar with the --listed-incremental option.

2) Each day I use it to write a new tar file (dated using a unix 
timestamp), using the snapshot file.

3) Each day it backs up a copy of new files into the new tar file 
(Great!)

4) Each day it also backs up a blank copy of *every* directory (just 
the directory name, not any files!) into the new tar file.

As I am backing up a root filesystem, there are thousands of 
directories, and they are bloating the daily tar files.  

Eg:

tar --list --bzip2 --file=www_archive_20030530_1054216915.tar.bz2

www/wwwarplus/
www/wwwarplus/cgi-bin/
www/wwwarplus/cgi-bin/arplus/
www/wwwarplus/cgi-bin/arplus/MIME/
www/wwwarplus/cgi-bin/arplus/data/
www/wwwarplus/htdocs/
www/wwwarplus/htdocs/arplus/
www/wwwarplus/htdocs/arplus/help/
www/wwwarplus/htdocs/arplus/images/
www/wwwarplus/htdocs/arplus/styles/
www/bb/bb.html
www/bb/bb2.html
www/bb/index.html

Every day, thousands of empty directories are included in the daily 
archive, when they were there in the first place, they got backed up 
in the first backup, and that should have been recorded in the 
snapshot file.  

I must be doing something wrong, because I doubt Tar would be backing 
up all those "directory names" each time for no good reason.

Thank you in advance for any advice you can offer!

Jason