Problems radeonfb, again...

I'm running an ATI OEM (Xelo) Radeon 8500 with a NEC MultiSync 1535VI panel connected via DVI-D. X runs well with the latest fglrx driver from ATI as well as with the OpenSource radeon driver. When booting, the framebuffer does not initialize (see below). With older versions of ATI's driver (fglr200) I also had problems with the panel-size-detection, too: I had to start X 3 to 10 times before it started fine. Once running, there were no further probs. Is there a possebility to skip the auto-detection of the panel size at boot time by setting it manual (via bootparams or compiling it into the kernel)?

--- Kernel output ---
radeonfb: ref_clk=2700, ref_div=12, xclk=25000 from BIOS
radeonfb: panel ID string: ªhé²^D
radeonfb: detected DFP panel size from BIOS: 1x0
radeonfb: Failed to detect DFP panel size
---------------------

thank you and excuse my poor english...
yours
-Daniel