After dist-upgrade xorg-driver-fglrx does not find valid screen modes anymore

Last dist-upgrade was Friday, September 30th. After dist-upgrade today
(Wednesday, October 5th) GDM / X would not be able not initialise the screen
anymore when using the "fglrx" driver. Disabling the "splash" kernel option does
not help; but the "ati" driver still works.

The Xorg.0.log file mentions the following, which might be of interest:
(II) Loading sub module "GLcore"
(II) LoadModule: "GLcore"
(II) Loading /usr/X11R6/lib/modules/extensions/libGLcore.a
Skipping "/usr/X11R6/lib/modules/extensions/libGLcore.a:m_debug_clip.o": No
symbols found
Skipping "/usr/X11R6/lib/modules/extensions/libGLcore.a:m_debug_norm.o": No
symbols found
Skipping "/usr/X11R6/lib/modules/extensions/libGLcore.a:m_debug_xform.o": No
symbols found
as well as
(II) Loading sub module "ddc"
(II) LoadModule: "ddc"
(II) Reloading /usr/X11R6/lib/modules/libddc.a
(II) fglrx(0): Connected Display1: LCD on internal LVDS
(II) fglrx(0): Display1 EDID data ---------------------------
(II) fglrx(0): Manufacturer: SEC Model: 3150 Serial#: 0
(II) fglrx(0): Year: 2003 Week: 0
(II) fglrx(0): EDID Version: 1.3
(II) fglrx(0): Digital Display Input
(II) fglrx(0): Max H-Image Size [cm]: horiz.: 33 vert.: 21
(II) fglrx(0): Gamma: 2.20
(II) fglrx(0): No DPMS capabilities specified; RGB/Color Display
(II) fglrx(0): First detailed timing is preferred mode
(II) fglrx(0): redX: 0.580 redY: 0.340 greenX: 0.310 greenY: 0.550
(II) fglrx(0): blueX: 0.155 blueY: 0.155 whiteX: 0.313 whiteY: 0.329
(II) fglrx(0): Manufacturer's mask: 0
(II) fglrx(0): Supported additional Video Mode:
(II) fglrx(0): clock: 119.2 MHz Image Size: 331 x 207 mm
(II) fglrx(0): h_active: 1680 h_sync: 1728 h_sync_end 1760 h_blank_end 1840
h_border: 0
(II) fglrx(0): v_active: 1050 v_sync: 1052 v_sync_end 1058 v_blanking: 1080
v_border: 0
(II) fglrx(0): 7T774154P1
(II) fglrx(0): º¯žŽr`@
(II) fglrx(0): End of Display1 EDID data --------------------
(WW) fglrx(0): Specified desktop setup not supported: 8
(II) fglrx(0): Primary Controller - LCD on internal LVDS
(II) fglrx(0): Internal Desktop Setting: 0x00000004
(==) fglrx(0): PseudoColor visuals disabled
(==) fglrx(0): Using gamma correction (1.0, 1.0, 1.0)
(==) fglrx(0): Center Mode is disabled
(==) fglrx(0): TMDS coherent mode is enabled
Cannot find any valid mode
(EE) fglrx(0): PreInitModes failed
(EE) fglrx(0): R200PreInit failed
(II) fglrx(0): === [R200PreInit] === end
(II) UnloadModule: "fglrx"
(II) UnloadModule: "ddc"
(II) UnloadModule: "vbe"
(II) UnloadModule: "int10"
(II) UnloadModule: "vgahw"
(II) Unloading /usr/X11R6/lib/modules/libvgahw.a
(EE) Screen(s) found, but none have a usable configuration.

Fatal server error:
no screens found