You can, if you can get the connectors. They use a UFL connector. But you'd either have to cut a hole in the casing to allow the wires to come out, or disassemble the laptop to route them to an opening, or to route them internally like they are with laptops designed with wireless. Once you have the wires routed outside, you could make any sort of antenna you want. I'm not sure how internal antennas are designed, they may just be the bare wires for all I know.
As for alexXx, pretty stupid response. Lots of things aren't possible even though you'd think they would be. Or vice versa.