configure-x.sh fails to set HorizSync and VertRefresh with sis driver

This affects thin clients using sis x.org driver and X_HORZSYNC and X_VERTREFRESH set in lts.conf. The problem was found on Hardy, but the script in question seems to be unchanged in Karmic.

When booting an ltsp client with X_HORZSYNC and X_VERTREFRESH set in lts.conf, the configure-x.sh script fails to add the HorizSync and VertRefresh options in the created xorg.conf as the sis driver adds similarly named options in the file.

The relevant options set in lts.conf are:
        X_HORZSYNC = 30-82
        X_VERTREFRESH = 56-76

When configure-x.sh runs "Xorg -configure", it creates xorg.conf.new that has section like this:

Section "Device"
        ...
        #Option "SecondMonitorHorizSync" # <str>
        #Option "SecondMonitorVertRefresh" # <str>
        ...
        Identifier "Card0"
        Driver "sis"
        VendorName "Silicon Integrated Systems [SiS]"
        BoardName "661/741/760 PCI/AGP or 662/761Gx PCIE VGA Display Adapter"
        BusID "PCI:1:0:0"
EndSection

In configure-x.sh the existence of the HorizSync and VertRefresh settings are checked like this:

if [ -z "$(grep HorizSync $INPUT_FILE)"] && [ -z "$(grep VertRefresh $INPUT_FILE)"];then

This matched HorizSync to SecondMonitorHorizSync and VertRefresh to SecondMonitorVertRefresh which in turn calls the wrong sed command. As a result the parameters are not added to /etc/X11/xorg.conf as they should.

The expected result in xorg.conf would be:

Section "Monitor"
VertRefresh 56-76
HorizSync 30-82
        Identifier "Monitor0"
        VendorName "Monitor Vendor"
        ModelName "Monitor Model"
EndSection

Instead it results in this:

Section "Monitor"
        Identifier "Monitor0"
        VendorName "Monitor Vendor"
        ModelName "Monitor Model"
EndSection

xorg.conf created by configure-x.sh attached