I can also confirm that this issue still exists in casper as of 2.04.2011. I am working with the BitDefender LiveCD (which uses casper) and have found that a PXE boot of the LiveCD does not update the /etc/resolv.conf.
I move, additionally, to excise the "manual" method from /etc/network/interfaces to avoid this issue moving forward.
I can also confirm that this issue still exists in casper as of 2.04.2011. I am working with the BitDefender LiveCD (which uses casper) and have found that a PXE boot of the LiveCD does not update the /etc/resolv.conf.
I move, additionally, to excise the "manual" method from /etc/network/ interfaces to avoid this issue moving forward.