tuning my startup sequence (xrandr)

Dear Group:

I recently upgraded to Ubuntu 12.04, and I'm running the Ratpoison
window manager (of course) - selected via lightdm at the login screen.

The problem is, this doesn't seem to give me the degree of control at
each execution phase that I would need to have startup work the way I
want.

 - .xinitrc isn't loaded
 - so I skip past that and conclude my .ratpoisonrc with "exec emacs"
 - then, from within my .emacs, I run "xrandr --output HDMI2 --auto
--left-of HDMI1" in order to get my dual-headed setup working
 - ... but this itself is not enough: I must then restart ratpoison in
order to have the two frames living side-by-side in the two monitors.
   - restarting ratpoison then creates a 2nd emacs, which I just kill

It seems that running the xrandr command from within the .ratpoisonrc
doesn't have the desired effect.

Could someone suggest a better way to run way to run xrandr?

Joe