[Xorg] RandR physical screen size question

[Aaron Plattner]

While working on rotation issues, I've noticed that xf86RandRGetInfo calculates
the physical screen size as
   
    pScreen->mmWidth * randrp->virtualX / scrp->currentMode->HDisplay,
    pScreen->mmHeight * randrp->virtualY / scrp->currentMode->VDisplay

in the case where the current mode is different from the screen's virtual size.
Originally, this function simply looked for any mode matching the virtual size,
but it was modified in response to XFree86's bug #853
(http://bugzilla.xfree86.org/show_bug.cgi?id=853).
This leads to the following behavior:

[aaron at dhcp-178-206 common]$ xrandr
 SZ:    Pixels          Physical       Refresh
*0   1280 x 1024   ( 361mm x 292mm )  *75   60
 1   1024 x 768    ( 361mm x 292mm )   85   75   70   60
[...]
 16   320 x 200    ( 361mm x 292mm )   85
 17   320 x 175    ( 361mm x 292mm )   85
Current rotation - left
Current reflection - none
Rotations possible - normal left inverted right
Reflections possible - none

[Hit ctrl-alt-+]

[aaron at dhcp-178-206 common]$ xrandr
 SZ:    Pixels          Physical       Refresh
 0   1280 x 1024   ( 361mm x 292mm )   75   60
 1   1024 x 768    ( 361mm x 292mm )   85   75   70   60
[...]
 16   320 x 200    ( 361mm x 292mm )   85
 17   320 x 175    ( 361mm x 292mm )   85
*18  1280 x 1024   ( 451mm x 389mm )  *75
Current rotation - left
Current reflection - none
Rotations possible - normal left inverted right
Reflections possible - none

Notice the new mode with the bogus physical size.

My question is, is this intentional, or a bug?  Why isn't the physical
size simply set to pScreen->mmWidth x pScreen->mmHeight?

Thanks!

-- Aaron Plattner