When I connect to any one of several ASA/Pix devices using the 4.9.01.0180 client on my Mac 10.5.6 machine DNS seems to get wonky.
I notice that /etc/resolv.conf changes (and in fact changes to the config for my home network) and drops the current local DNS and any manually entered DNS servers.
I have found no way to change this in the Client. I manage the firewalls I'm connecting to and know that they are not handing out my home's DNS server.
SOMETIMES immediately after a reboot the issue doesn't present itself.
Otherwise there don't seem to be issues with the Mac or the firewalls I'm connecting to.