My Brother DCP-1200 multifunction printer will not scan legal size documents

I have a Brother DCP-1200 mfc printer that worked beautifully when I ran W98SE. I got a new DELL (the company stinks) P4 2.8 MHz running WXP. There are no separate drivers for the printer, instead it adopts Microsoft's. I am told that the TWAIN drivers in XP can only recognize letter size paper for scanners, and not legal. I contacted Brother who told me to contact Microsoft who told me to contact DELL because XP is OEM and therefore DELL has to give me support. After 2 1/2 hours with some tech with a heavy Indian accent (no offense, but DELL clearly outsources to India), I was told that they couldn't help me. Does anyone have any suggestions? Thx.