--- ../pam_radius-1.3.17 (2)/USAGE	2007-03-26 07:35:31.000000000 +0200
+++ USAGE	2011-01-03 15:05:07.455498750 +0100
@@ -83,5 +83,10 @@
                  validated.  This option will probably only be necessary
                  on REALLY OLD (i.e. Livingston 1.16) servers.
 
+filter_id=foo,bar - When used the attribute type 11 (Filter-Id) of the
+                    server response is compared with the comma separated
+                    list (up too 20 tokens). If the response is included 
+                    in the list return success, if not return failure.
+
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