yes, there is an undocumented command line parameter available
usage:
-res [width] [height] -bpp [color depth]
example:
-res 1280 1024 -bpp 32
but it seems to keeps resetting the resolution to 800x600x16 if an invalid/unsupported resolution was entered
edit: what i had in theory was if there is an 1280x960 mode supported in the drivers, armada 2 prefers that mode OVER 1280x1024, as i cannot choose 1280x960 in my display settings but only 1280x1024.
maybe if someone kills 1280x960 out of their directx supported resolutions list, it *may* work.

i used directx control panel that is included in the directx 9 sdk to read the supported resolutions for directdraw. a standalone version can be downloaded
here