Description of problem:
If nss-mdns had been installed already when executing ipa-client-setup, the mdns4_minimal entry for hosts in /etc/nsswitch.conf seems to be overwritten.

Version-Release number of selected component (if applicable):
freeipa-client-2.0.0.rc3-0.fc14.x86_64

How reproducible:
Tried with one client

Steps to Reproduce:
1. Install nss-mdns when ipa-client-setup had not been run
2. Run ipa-client-setup
  
Actual results:
ping somehost.local does not work anymore, i.e. lookup of mDNS names without specific code to call Avahi does not work anymore.

Expected results:
Lookup via mDNS should still work.

Additional info:
Since I'm currently testing for our setup I have only one host I tried it on. Reinstalling nss-mdns fixes the problem. The only reason that I see atm that could have changed this is freeipa-client. I won't have another testing machine for some time, maybe you can give it a try on a development machine.