page fault in g_event (probably zfs related?)

Hi,

i had a working zpool which consisted of only 1 drive (ad6), then i
added another drive (da1) to it and the zpool increased in size as
expected. Every thing worked fine until i had to reboot the system.

Now every time after the da1 disk is probed i get this:

Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 00
fault virtual address      = 0x3f80
fault code              = supervisor read, page not present
instruction pointer     = 0x20:0xc073bfe4
stack pointer           = 0x28:0xd17aab60
frame pointer           = 0x28:0xd17aac58
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, def32 1, gran 1
processor eflags        = interrupt enabled, resume, IOPL = 0
current process         = 2 (g_event)
[thread pid 2 tid 100012 ]
Stopped at      bcmp+0x14:      repe cmpsl      (%esi),%es:(%edi)
db> where
Tracing pid 2 tid 100012 td 0xc27f1aa0
bcmp(c2e28e00,c2acc280,c07b5138,0,c296acd8,...) at bcmp+0x14
g_part_taste(c07b5040,c296ac80,0,c2af2900,0,...) at g_part_taste+0x1e3
g_new_provider_event(c296ac80,0,0,0,ffffffff,...) at
g_new_provider_event+0x64
g_run_events(c07f1d00,0,4c,c077c981,64,...) at g_run_events+0x2b5
g_event_procbody(0,d17aad38,0,0,0,...) at g_event_procbody+0x6b
fork_exit(c0542a30,0,d17aad38) at fork_exit+0x99
fork_trampoline() at fork_trampoline+0x8
--- trap 0, eip = 0, esp = 0xd17aad70, ebp = 0 ---

ad6 is an ATA drive connected to an internal ATA Controller:

ad6: 239372MB <Maxtor 6L250R0 BAH41G10> at ata3-master UDMA66

da1 is an SATA drive in an external USB enclosure:

umass0: <Sunplus Technology Inc. USB to Serial-ATA bridge, class 0/0,
rev 2.00/ec.02, addr 2> on uhub0
da1 at umass-sim0 bus 0 target 0 lun 0
da1: <ST912082 1AS > Fixed Direct Access SCSI-2 device
da1: 1.000MB/s transfers
da1: 114473MB (234441648 512 byte sectors: 255H 63S/T 14593C)

The system is a 2 CPU SMP system running -CURRENT as of yesterday.

I'll leave the system in this state in case anyone would like to have
additional information from the debugger.

Cheers,
Flo