WEP keys can be cracked within about 45 minutes using one (or two) notebook computers with cracking software readily available free on the Internet. BT technical people MUST know this, if they don't then their whole pretense of security is a complete sham.

http://www.google.co.uk/search?hl=en&q=cracking+WEP&btnG=Google+Search
Link

WEP encryption was once upon a time adequate, nowadays its about as useful as securing your front door with a bit of string, tied in a knot.

Villains could sit in a van in your street for about an hour then download all your letters and emails and learn credit card details, bank details, and even more useful any holiday bookings. With the latter they would know when you will be away so they can bring a furniture van and burgle everything from your house.

===========
You are advised to upgrade the security settings in your BT Home hub to use WPS-PSK instead. If you don't know how, phone up the BT support line. If they get enough such calls saying the gist of the above message, BT might change the default settings from WEP to WPA, before too many users are compromised.

Bill.