startx not passing options to server?

["Keith G. Murphy" <keithmur@mindspring.com>]

I recently downgraded from XFree 4 to 3.3.6 (the one in Potato).  I also
made sure to downgrade xbase-clients and xserver-svga (the server I'm
using).  Then, I recreated my XF86Config file.

I have my XF86Config file set up so that there is only one resolution
choice for each color depth.  That way, I can simply use the '-bpp'
option to force X to use a particular resolution as well as color
depth.  This all worked fine under version 4.

But now, when I do

startx -- -bpp <depth>

it does not choose the desired color depth and resolution.  It always
goes to the default depth that I specify in XF86Config.  The error
output shows no sign that it tried and rejected a particular depth or
resolution.

However, 

X -bpp <depth>

chooses the color depth and resolution just fine, as the error output
shows me.

Has anyone seen this before?  Where should I start looking for a handle
on this problem?  It might be because of the "downgrade"; I really don't
know.

TIA.