Archive extraction issues

[Johan Booysen]

I'm trying to use tar to (sort of) make an incremental backup of a
directory which contains subdirectories and a couple of other tar
archives:
tar -cvf incremental.tar --newer-mtime "11 Oct 2007" *
 
This works the way I want it to, but I've noticed that when I later
extract the incremental.tar file (which contains other tar archives)
then in that process it also extracts the other tar archives it
contains.
 
Is there a way of getting tar to NOT extract the member archives?  I've
read the man pages and googled on this issue but can't get it to work.
 
Thanks.