X crashing when resuming

Hello,

I'm having an annoying problem with XFree86 V4.3. Upon resume from S3 it 
crashes in one out of two cases. The short error follows below, the full 
log may be found at http://www.lestinsky.de/michael/XFree86.0.log

When this happens I can't switch to another console, the screen remains 
dark (backlight off). But I can log in from remote.

I'm 99% sure it happens allways when resuming for the second time. The
first time worked so far in most cases. 

The system is a Samsung X05 notebook with i855GM graphics running a week
old -current and a relatively fresh XFree86 installation from ports.
Resume only works with "sysctl hw.acpi.reset_video=0" or the kernel would 
lock hard before reenabling the console.

Any ideas?

Thanks,
Michael

==================== Excerpt from XFree86.0.log ==========================

Error in I830WaitLpRing(), now is 5241, start is 3240
pgetbl_ctl: 0xfee0001 pgetbl_err: 0xfb15c019
ipeir: 0 iphdr: 55300006
LP ring tail: c48 head: 0 len: 1f001 start 7fde000
eir: 0 esr: 11 emr: ffff
instdone: ffc1 instpm: 0
memmode: 307 instps: 20
hwstam: ffff ier: 0 imr: ffff iir: 0
space: 127920 wanted 131064

Fatal server error:
lockup


When reporting a problem related to a server crash, please send
the full server output, not just the last messages.
This can be found in the log file "/var/log/XFree86.0.log".
Please report problems to xfree86_at_xfree86.org.

Error in I830WaitLpRing(), now is 7243, start is 5242
pgetbl_ctl: 0xfee0001 pgetbl_err: 0xfb15c019
ipeir: 0 iphdr: 55300006
LP ring tail: c50 head: 0 len: 1f001 start 7fde000
eir: 0 esr: 11 emr: ffff
instdone: ffc1 instpm: 0
memmode: 307 instps: 20
hwstam: ffff ier: 0 imr: ffff iir: 0
space: 127912 wanted 131064

FatalError re-entered, aborting
lockup


=============================== dmesg ====================================

wakeup from sleeping state (slept 00:00:20)
cpu0: Cx states changed
ums0: at uhub0 port 2 (addr 2) disconnected
ums0: detached
Status is 0x30000006
Status is 0x30000006
    ACPI-0440: *** Error: Handler for [EmbeddedControl] returned AE_NO_HARDWARE_RESPONSE
    ACPI-1303: *** Error: Method execution failed [\\_TZ_.THRM._TMP] (Node 0xc2a46d80), AE_NO_HARDWARE_RESPONSE
ums0: Logitech Optical USB Mouse, rev 2.00/3.40, addr 2, iclass 3/1
ums0: 3 buttons and Z dir.
pid 810 (XFree86), uid 0: exited on signal 6