--- ippool.sql  2009-01-29 22:33:12.000000000 +0100
+++ ippooln.sql 2009-01-29 22:39:22.000000000 +0100
@@ -8,7 +8,7 @@
   nasipaddress varchar(15) NOT NULL default '',
   calledstationid VARCHAR(30) NOT NULL,
   callingstationid VARCHAR(30) NOT NULL,
-  expiry_time DATETIME NULL default NULL,
+  expiry_time TIMESTAMP NOT NULL default CURRENT_TIMESTAMP,
   username varchar(64) NOT NULL default '',
   pool_key varchar(30) NOT NULL,
   PRIMARY KEY (id)