+First make sure your Mozilla distribution contains the Negotiateauth component
+(libnegotiateauth.so on Unix, negotiateauth.dll on Windows). Generally this is
+included in versions 1.7beta and later on Unix platforms including Mac OSX,
+maybe 1.8 and later on Windows.)
+
+If you want to find out what happens in the Negotiateauth component use
+following environment variables:
+ NSPR_LOG_MODULES=negotiateauth:5
+ NSPR_LOG_FILE=/tmp/negotiateauth.log
+before starting Mozilla. You will see debugging messages logged in the file
+specified by NSPR_LOG_FILE (/tmp/negotiateauth.log)