Print defaults on server not set on client

Hi all -

I'm a little puzzled by what appears to be a changing behavior of our
print servers.

Last August we implemented 40 multifunction copier\printer\scanner\fax
devices. ~30 of them have color print capability, which is expensive
compared to B&W printing. So at the print server, we changed the
default driver configuration from Color to B&W (we didn't bar a user
from printing in color, just required s/he make a change to the driver
at print time).

My testing, and experience since August seemed to show that if a user
changed their printer preferences to permanently print in color, that
the next time they logged on, the print server would re-install the
B&W configuration.

Recently (which may be January 2008) the color print configurations
have been sticking.

So - first - Does anyone know if my assumptions are correct? Should
the printer preferences set in the advanced tab on the print server
overwrite the local user setting?

In December we upgraded our 2k3 servers to R2 - might this upgrade be
responsible?

Thanks in advance -

Rob