Joel, your title is a little confusing. T-Max is a B&W film that requires real B&W processing. T400 CN is a B&W film that requires regular one hour color developing (C-41). Sounds like to me that you are referring to T400 CN.(posted 8656 days ago)According to Kodak, T400 CN negatives can be printed with regular B&W paper (assuming with normal enlarger and wet work). They also can be printed by the color lab machine (RA-4 process). Wolfram hit it on the head. The standard filter setup for color prints will yield T400 CN prints with a sepia tone. If your lab processor is knowledgable, they can adjust the filtration so that the prints can be neutral or with any color cast you want. Facts gleaned from:
http://www.kodak.com/global/en/professional/products/films/t400cn/qAnd A.shtml
Sounds like to me that your lab is lazy or doesn't know how to do it. You might want to look into another lab if you don't like the sepia toned prints.