[Exim] Spam Control

    I have heard various (somewhat similar) posts on spam control. What would 
be a proper way for - University type environment I notice alot of British 
University mail admins on the list - to block out spam. If I have to read 
certain parts of the FTM please point me in the right direction even if I 
have to go any web sites please direct me to the correct ones.

    What exact steps should one take using Exim. Thank you for all you input 
and advice.

    Cheers,

    Aly.