yum: recurring error 256 on nfs mounted repo

We have some special built rpms that were grabbed by an update on one 
machine.  The local repo is nfs mounted.  For some reason, the network 
stopped working on the machine in the middle of an update.  I restarted 
the network, cleared the nfs mounts and remounted them and everything 
seemed fine except for the packages coming from the local repo (nfs).  
Now even though the mounts are fine and the packages are fully available 
and I even copied them back and forth over the mounts, yum still gives 
us an error 256 and I cannot find out how to get it to quit doing that.  
I've tried expiring the cache.  No change.  My next thing is to do a 
full yum clean all, but I was hoping to avoid that with so many packages 
and only two that are a problem.  What can clear this error?

Regards,
Gerry