Connect Asterisk with Nokia E63

Hello,
I have been figuring out to connect my cell phone Nokia E63 to my asterisk box  over a wifi network and finally I got it actually its not as hard just follow the steps below
If you have Nokia E63

go to the Tool>>Setting>>Connection>>Sip Settings

Chose New SIP Profile.
Profile Name =  name it anything as you wish
Service Profile = IETF
Default Access point = choose your wifi connection
Public User name = asterisk sip extension, in my case it is 200
Use Compression = No
Registration = Always on
Use Security = No
Proxy Server:
Proxy Server Address: Your Asterisk Machine IP address
Realm=asterisk
username= your sip extension in asterisk
Password= your sip extension password
Allow loose routing = Yes
Transport Type = Auto
Port = 5060
Register Server
Register Server address = your asterisk machine IP

Realm=asterisk
username= your sip extension in asterisk
Password= your sip extension password
Transport Type = Auto
Once you finished all these setting press back and on SIP setting menu you'd see the status as
Registered (Wifi Network only)

now to make a call you need to do little things more,

go to Tools>>Settings>Connections>>Internet tel.

and create a new profile and select this SIP Profile and press back

The great thing about Nokia E63 is it can automatically switch between voice GSM mode and Internet mode. This feature may also be there in others Nokia model but I only know about E63.
Now to get this go to the
Tools>>Settings>Phone>>Call
Default call type=Internet call

and in the Network option select dual mode
Now if I am in office my cell phone act as my local extensions and I send receive calls using landline and If I am at home I am connected to my SIP server and can make a cheap/almost free calls internationally.