Multiple Connections for One UserID

Let me preface this with the required "I'm pretty much a newbie to freeRADIUS"... Can someone point me to the place where I can modify the number of simultaneous connections that are allowed per user? I've just now noticed that I am currently only allowed a single connection and I'd like to increase that value. Even better, can someone recommend a good resource (book, website, etc.) to supplement the freeRADIUS website? My configuration is being used to authenticate DSL connections - I have modems that terminate on an Alcatel DSLAM which are aggregated at at Juniper ERX router. The router uses the freeRADIUS configuration for auth. Thanks! -Samson