Laser printing B/W when color is out

[glemu]

Hi,
My current Lexmark C540n prevents me from printing B/W, when one of the color cartridges are out, even when I choose B/W printing.
Is there a trick, to cheat the printer?

Alternatively I am considering a replacement. Any recommendations for a budget network color laser printer, preferably with a scanner, that allows B/W printing when one cartridge is out?

Thanks
Glenn