diff -up ./denyhosts.py.orig ./denyhosts.py
--- ./denyhosts.py.orig	2012-01-30 13:14:41.146715839 -0600
+++ ./denyhosts.py	2012-01-30 14:45:14.372539341 -0600
@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 import os
+import platform
 import sys
 
 import DenyHosts.python_version
@@ -107,6 +108,10 @@ if __name__ == '__main__':
             print "DenyHosts version:", VERSION
             sys.exit(0)
 
+    # This is generally expected to be in the environment, but there's no
+    # non-hackish way to get systemd to set it, so just hack it in here.
+    os.environ['HOSTNAME'] = platform.node()
+
     prefs = Prefs(config_file)    
             
     first_time = 0