aac & PAE not happy in -current

I've got a Dell PowerEdge 2650 running the 200702 -current snapshot.  
It's fine with 2GB of ram, but when I tried bumping it to 6GB and  
turning on PAE, the aac driver panics on boot.

aacch0: <AAC RAID Channel> port 0xcc00-0xccff mem  
0xfccff000-0xfccfffff irq 30 at device 6.0 on pci5
aacch1: <AAC RAID Channel> port 0xc800-0xc8ff mem  
0xfccfe000-0xfccfefff irq 31 at device 6.1 on pci5
aac0: <Dell PERC 3/Di> mem 0xf0000000-0xf7ffffff irq 30 at device 8.1  
on pci4
panic: pmap_mapdev: Couldn't alloc kernel virtual memory

Backtrace:

pmap_mapdev
nexus_activate_resource
bus_generic_activate_resource
bus_generic_activate_resource
bus_generic_activate_resource
pci_alloc_resource
bus_alloc_resource
aac_pci_attach
device_attach
device_probe_and_attach
bus_generic_attach
pci_attach
device_attach
device_probe_and_attach
bus_generic_attach
mptable_hostb_attach
nexus_attach
...

Booting the same kernel without PAE I get the same thing:

aacch0: <AAC RAID Channel> port 0xcc00-0xccff mem  
0xfccff000-0xfccfffff irq 30 at device 6.0 on pci5
aacch1: <AAC RAID Channel> port 0xc800-0xc8ff mem  
0xfccfe000-0xfccfefff irq 31 at device 6.1 on pci5
aac0: <Dell PERC 3/Di> mem 0xf0000000-0xf7ffffff irq 30 at device 8.1  
on pci4
aac0: [FAST]
aac0: Adaptec Raid Controller 2.0.0-1

and it works fine.


Is this a known problem, or is there any other info I can give? Happy  
to try anything anyone might suggest. :)


-- Kevin