virtual machine - How to assign an INTERNAL Wifi Adapter to the guest OS in VM?

I'm having trouble assigning my Host Wifi Adapter (which is installed internally in my laptop) DIRECT to the guest OS [Windows XP x86] in the Oracle VirtualBox VM.

I tried so many ways, like Bridging, NAT and etc. But only Bridging sort of worked, but it wasn't a direct assigning, my Host OS [Windows 7 x86] was still able to use WiFi and connect wireless networks, whereas in the guest OS I wasn't able to even see the available wireless networks list.

In several forums I found out the conclusion that only assigning the external WiFi adapters (like USB-Stick) to the Virtual Machines is possible.

Any ideas?