Timer issues when running CURRENT inside qemu

Hello, 
I'm using the latest qemu release (0.10.0) to simulate network boot of the
FreeBSD diskless station. Recent qemu supports HPET timer emulation (and
does it by default). 

I've found something that could be interesting to -CURRENT developers...

When I boot a 8.0-CURRENT kernel I've got console and dmesg full of such
information:

calcru: runtime went backwards from 981954 usec to 282875 usec for pid 14
(sh)  
calcru: runtime went backwards from 11248014703054744 usec to 23653848 usec
forpid 14 (sh)                                                             
       
calcru: runtime went backwards from 1298297 usec to 909205 usec for pid 11
(intr)                                                                     
         
calcru: runtime went backwards from 11248014678717988 usec to 119242 usec
for pid 60 (ps)                                                            
          
calcru: runtime went backwards from 11248014678921829 usec to 2516605 usec
for pid 60 (ps)                                                            
         
calcru: runtime went backwards from 7014844 usec to 6270851 usec for pid 0
(kernel)                                                                   
         
calcru: runtime went backwards from 11248014678723366 usec to 31380 usec
for pid 15 (nfsiod 0)                                                      
           
calcru: runtime went backwards from 22496029384944496 usec to 37978168 usec
for pid 14 (sh)                                                            
        

I also get events like this (which makes my console session die, or for
example ssh to fail):
login: Mar 11 21:15:12 qemu kernel: pid 831 (getty), uid 0, was killed:
exceeded maximum CPU limit 

Sysctl shows these timers.

qemu% sysctl kern.timecounter.choice
kern.timecounter.choice: TSC(800) HPET(900) ACPI-safe(850) i8254(0)
dummy(-1000000)

I tried to switch between them, but any of them helps.

I don't remember experiencing such things when running 7.x or 6.x series so
maybe it's a new issue.

It happens regardless of kqemu usage.

Of course if you find this interesting and need some more info from dmesg
or sth - I'm at your service :)

-- 
Regards,
Jedrzej Kalinowski