[tools] mrepo not creating metadata for old yum

[urgrue]

I've got mrepo set up and serving rhel as5 (this works). Im trying to
add 4WS and 4AS. These don't. I think the reason is because mrepo is not
creating the headers file/dir that yum wants.
My 4AS and 4WS clients use yum 2.0.7, and the 4AS section in my
mrepo.conf contains metadata = yum repomd repoview

Running mrepo -ugvv it doesn't complain about anything, and successfully
downloads updates and also creates the repodata directory for newer yum.
But I don't see the headers dir for older yum.

Client-side it looks like this:
retrygrab() failed for:
  http://mrepo.server.com/mrepo/4WS-i386/RPMS.all/headers/header.info
  Executing failover method
failover: out of servers to try
Error getting file
http://install.elma.fi/mrepo/4WS-i386/RPMS.all/headers/header.info
[Errno 4] IOError: HTTP Error 404: Not Found

Any ideas?