dumping non-continuous ranges using svnadmin dump

I have a repository called "sandbox" whose HEAD is at revision 20. I would
like to dump revisions 1 to15 and then from 18 to19. Basically I want to
skip revision 16,17 and 20.
The command:

# svnadmin dump -r 1:15 -r 18:19 sandbox > sanbox-dumpfile

gives error message:
svnadmin: Multiple revision arguments encountered; try '-r N:M' instead of
'-r N -r M'
and the command:
#svnadmin dump -r 1:15,18:19 sandbox > sanbox-dumpfile

gives error message:
svnadmin: Syntax error in revision argument '1:15,18:19'
How can I do this?

Thanks.
Received on 2010-10-02 04:07:00 CEST