create channel, exclude packages in dir.

In most environments, this is probably not a big deal... let me explain
my scenario:

We maintain a redhat mirror in our department.  My 'Current' server
mounts the 'updates' directory located on the mirror (on a separate
interface from the public one) ;-)  So when Redhat pushes out updates,
it updates the directory pointed to by my current server.  I need to
know how to deal with this.

Is there a way to somehow exclude packages that are located in the
directory when I run 'create_channel' without changing the perms or
removing the packages? (they need to stay put - it's a mirror!).  

An example:  I don't want my users running up2date, and upgrading to an
incompatible version of up2date, but I can't change the permissions or
remove the package.  I haven't run 'create_channel' yet to update what
gets pushed out from the current server, so as of now, this isn't an
issue.  But this sounds like problems to me, because what's going to
happen when my current server, which thinks certain packages are there,
tries to deliver them only to find that they're not - or they're not the
same version as before?

Also, *is* there a way to accomplish the exclusion of packages from a
channel while still having them in the channel directory?

Sorry if I missed this in the docs.  Links to RTFM on whatever I missed
are more than welcome.

brian.
-- 

Brian K. Jones
System Administrator
Dept. of Computer Science, Princeton University
http://www.linuxlaboratory.org
[email protected]
Voice: (609) 258-6080