wi0 - really need help

Hello all.
Something strange happens with my vaio pcg-v505bx laptop tonight. It
has wireless NIC, so I use it in infrastructure mode, connecting to
d-link dwl-900ap+.
Tonight, i was sitting surfing web, reading maillists, etc, as usual.
Wireless connection was perfect (as usual). Suddenly I decide to scan
my freebsd NAT gateway due to it's network reconfiguration. So, while
sending nmap packets to AP over the air, my wireless connection
suddenly became broken (btw, I don't know was it related with nmap scanning or not).
wi0 was up and running but ping didn't work, etc. Huh, I had such kind
of troubles several days ago while using linux 2.4.25 (there are 2
oses installed onto laptop) while transfering big files over the air,
but it was linux driver problem, and freebsd's wi0 always works
perfect (thank you, fbsd folks). So I just kldunload and kldload
if_wi.ko again, and reconfigure my wi0 iface. But it didn't help. And the trouble is in a strange
string I didn't seen before - wi0: [GIANT-LOCKED]

This is a full wi0-prelated part of dmesg:

wi0: <Intersil Prism2.5> mem 0xf8000000-0xf8000fff at device 2.0 on pci2
wi0: [GIANT-LOCKED]
wi0: using RF:PRISM2.5 MAC:ISL3874A(Mini-PCI)
wi0: Intersil Firmware: Primary (1.1.0), Station (1.4.3)
wi0: Ethernet address: 00:d0:59:49:12:52
wi0: 11b rates: 1Mbps 2Mbps 5.5Mbps 11Mbps

So now AP detects that my laptop come onto the stage (I can see
"Wireless PC connected 00-D0-59-49-12-52" in ap logs), but wireless
network is dead. I tried reboot, poweroff, reboot to linux, etc, but
no luck. It looks like I killed this piece of hardware with software
packets :-\

Would you mind to explain what [GIANT-LOCKED] is? And what can I do?
All advices are VERY welcomed :(
  

-- 
Best regards,
 Toxa                          mailto:postfix_at_sendmail.ru