Assertion `fd && fd->magic == 0x04463138'

Hello,

I'm using yum to udpate ~2000 rpms and around the ~1000 rpm
I usually get :

Assertion `fd && fd->magic == 0x04463138'

A bit of googeling shows thats a limitation of the
open file handles, which is 1024.
So setting ulimit -n 8192 fixes the problem, but I think
that yum/rpm (?) has a filedescriptor leak somewhere.

Is this right?
Can it be fixed?

There a many fds in the state "CLOSEWAIT"
and all seem to be open:

pxe3:~ # lsof -p 5384 | grep http | wc -l
1788

regards,

Martin