xrandr reports invalid refresh rates for MergedFB setup

This bug probably causes bugs in screen resolution switcher (bug #41610) and resapplet (bug #41607) packages (crashes when trying to change the resolution).

The bug affects gnome-control-center package from Main. Maybe this bug is even caused by something weird in xserver-xorg or any xorg-related package?

notebook HP compaq nc6000 (1400x1050) + external 19" LCD HP 1902 (1280x1024)
ATI Technologies Inc RV350 [Mobility Radeon 9600 M10]
Linux sarim 2.6.15-21-686 #1 SMP PREEMPT Fri Apr 21 16:57:03 UTC 2006 i686 GNU/Linux => up-to-date Dapper Drake preview

xserver-xorg 7.0.0-0ubuntu2
resapplet 0.0.7+cvs2005
xserver-xorg-driver-ati 6.5.7.3-0ubuntu5
xrandr 1.0.1-0ubuntu1

sarim:~$ xrandr
 SZ: Pixels Physical Refresh
 0 2680 x 1050 ( 681mm x 267mm ) 6895
*1 1400 x 1050 ( 681mm x 267mm ) *-19554
Current rotation - normal
Current reflection - none
Rotations possible - normal
Reflections possible - none

see the negative refresh in current mode and too high refresh in alternative mode. xrandr is able to switch the modes without problems but the graphical tools in Gnome are confused by invalid refresh rates and crash.

xorg.conf snip:

Section "Device"
        Identifier "Radeon Mobility 9600 MergedFB"
        Driver "radeon"
        BusID "PCI:1:0:0"
        Option "MergedFB" "true"
        Option "CRT2HSsync" "30-80"
        Option "CRT2VRefresh" "59-85"
        Option "MonitorLayout" "LVDS,TMDS"
        Option "OverlayOnCRT2" "true"
        Option "MetaModes" "1400x1050-1280x1024 1400x1050"
        Option "MergedNonRectangular" "true"
        Option "CRT2Position" "RightOf"
        Option "MergedDPI" "100 100"
        Option "DynamicClocks" "true"
        Option "BIOSHotkeys" "true"
EndSection

Section "Monitor"
        Identifier "Generic LCD"
        Option "DPMS"
        Option "DDCMode" "on"
EndSection

Section "Screen"
        Identifier "MergedFB Screen"
        Device "Radeon Mobility 9600 MergedFB"
        Monitor "Generic LCD"
        DefaultDepth 24
        SubSection "Display"
                Depth 24
                Modes "1400x1050"
        EndSubSection
EndSection