Clock not moving in virtual machine

Hi,

I have a VPS from rootbsd.net which is running current, though I don't
update it very often. I just built and installed a new world and
kernel and now the clock will not move from the time the system was
booted, ie:
# date
Thu Jul 15 16:15:58 PDT 2010
<wait a minute>
# date
Thu Jul 15 16:15:58 PDT 2010

I have an old kernel from May 27 which doesn't have this problem. I
noticed some clock related stuff changing in current in the last
couple of weeks and suspect that their VM setup doesn't play well with
these changes (their site says they use Xen, but several boot messages
refer to QEMU). Officially, I think they only support running 8.0 so I
thought I would ask here if anyone has any ideas before putting in a
support request.

Here's a diff of the dmesgs - I can post full copies if needed but
didn't want to start with a ridicously long message:

--- dmesg.old	2010-07-15 17:45:20.000000000 -0700
+++ dmesg.new	2010-07-15 17:46:45.000000000 -0700
_at__at_ -2,10 +2,9 _at__at_
 Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
 	The Regents of the University of California. All rights reserved.
 FreeBSD is a registered trademark of The FreeBSD Foundation.
-FreeBSD 9.0-CURRENT #0: Thu May 27 01:26:08 PDT 2010
+FreeBSD 9.0-CURRENT #0: Thu Jul 15 16:13:28 PDT 2010
     rfarmer_at_peridot.predatorlabs.net:/usr/obj/usr/src/sys/PERIDOT i386
-Timecounter "i8254" frequency 1193182 Hz quality 0
-CPU: Intel(R) Xeon(R) CPU           E5520  _at_ 2.27GHz (2261.02-MHz
686-class CPU)
+CPU: Intel(R) Xeon(R) CPU           E5520  _at_ 2.27GHz (2261.59-MHz
686-class CPU)
   Origin = "GenuineIntel"  Id = 0x106a5  Family = 6  Model = 1a  Stepping = 5
   Features=0x1781fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,MMX,FXSR,SSE,SSE2,HTT>
   Features2=0x80182201<SSE3,SSSE3,CX16,SSE4.1,SSE4.2,<b31>>
_at__at_ -13,9 +12,10 _at__at_
   AMD Features2=0x1<LAHF>
   TSC: P-state invariant
 real memory  = 268435456 (256 MB)
-avail memory = 252473344 (240 MB)
-ACPI Error: A valid RSDP was not found (20100428/tbxfroot-309)
+avail memory = 252444672 (240 MB)
+ACPI Error: A valid RSDP was not found (20100702/tbxfroot-309)
 MPTable: <_HVMCPU_ XEN         >
+Event timer "LAPIC" frequency 0 Hz quality 500
 FreeBSD/SMP: Multiprocessor System Detected: 2 CPUs
 FreeBSD/SMP: 0 package(s) x 16 core(s) x 2 SMT threads
  cpu0 (BSP): APIC ID:  0
_at__at_ -26,7 +26,7 _at__at_
 ioapic0: Assuming intbase of 0
 ioapic0 <Version 1.1> irqs 0-47 on motherboard
 kbd1 at kbdmux0
-ACPI Error: A valid RSDP was not found (20100428/tbxfroot-309)
+ACPI Error: A valid RSDP was not found (20100702/tbxfroot-309)
 ACPI: Table initialisation failed: AE_NOT_FOUND
 ACPI: Try disabling either ACPI or apic support.
 pcib0: <Host to PCI bridge> pcibus 0 on motherboard
_at__at_ -81,7 +81,10 _at__at_
 ppc0: Generic chipset (NIBBLE-only) in COMPATIBLE mode
 ppc0: [ITHREAD]
 ppbus0: <Parallel port bus> on ppc0
-atrtc0: <AT Real Time Clock> at port 0x70 irq 8 on isa0
+atrtc0: <AT realtime clock> at port 0x70 irq 8 on isa0
+atrtc0: [FILTER]
+Event timer "RTC" frequency 32768 Hz quality 0
+Starting kernel event timers: LAPIC _at_ 200Hz, RTC _at_ 128Hz
 Timecounters tick every 5.000 msec
 ad0: 10240MB <QEMU HARDDISK 0.10.2> at ata0-master WDMA2
 SMP: AP CPU #1 Launched!

Thanks,
-- 
Rob Farmer