Follow the SUN ... Ajay - The Main Event, The Headliner, The Showstopper (^_^)

Usually the NIC Lan Card & wi-fi card drivers will be detected by default, so all you need is to go :
Start==>Administration ==> Networks ==> Wireless or Ethernet ==> properties ==> enable this connection, select the Network from the available networks, keytype- hexadecimal, configuration-DHCP If you want to auto-enable this wifi connection then check 'enable on boot'. Now select 'Activate' and you are done. Surf Net !!!

In my HP nx6315 laptop we're having broadcom NIC card 'bcm4401' series. It was not that difficult I followed the procedure below :

Downloaded bfe 2.3 from here : http://opensolaris.org/os/community/device_drivers/files/bfe-2.3.1t0.tar.gz
Extracted it in a folder & executed these commands.

make
make install
./adddrv.sh
modload obj/bfe
modinfo  |  grep bfe (loaded?)
devfsadm -i bfe
ifconfig bfe0 plumb
ifconfig bfe0 up

Now , Start==>administration ==> Networks ==> Ethernet ==> properties ==>
enable this connection, select the Network from the available networks, keytype- hexadecimal, configuration-DHCP
If you want to auto-enable this wifi connection then check 'enable on boot'. Now select 'Activate' and you are done.
Surf Net !!!

Or if this doesn't work then please visit this link :
http://www-user.uni-bremen.de/~hburde/solaris_bmc4401.html