identify antenna

Does anyone recognise this antenna, in the image ?
It's mounted high up on the wall of a factory unit being taken over by a client.
I assume it's some sort of WiFi antenna.
There is an ethernet cable plugged in about maybe 10 metres away which disappears into the wall - I'm guessing this might be related, but that's just a guess.

[IMG]http://i46.tinypic.com/2l8cemq.jpg[/IMG]

From your picture that looks to me like a GSM (mobile phone) aerial

Thanks Vivaciti, that does make sense given the location.