〜　喫煙されるお客様へ　〜      構内は禁煙になっております    外の喫煙コーナーでお願いします。

The gist (but politely): "To customers who smoke: This is a non-smoking area, please use the smoking corner outside."  A blogger took the time to compare various automatic translators. Here are his results fyi:

[Babelfish]
    - To the customer who smokes -
    the enclosure we have become prohibition of smoking,
    we ask with the smoking corner outside.
[Google]
    Smoking to be one of your
    Smoking is on the premises,
    In the smoking area outside.
[Reverso]
    I ask a smoked visitor for the yard at the outside smoking corner that smoking is prohibited in.
[Paralink]
    Customers will be smoking on campus is a non-smoking, smoking outside corner.
[Windows Live]
    and smoking that is customer to premises smoking and: on the outside smoking corner in.
[OCN]
    Premises at the outside smoking
    area which becomes no smoking
    to the customer who smokes, please.
[@Nifty]
    - Visitor smoked -
    please give me premises in the outer smoking corner which is giving up smoking.
[Excite]
    To the customer from whom it smokes
    I hope premises in the smoking corner of the outside that is no
    smoking.

Kind of like reading modern poetry.