ERROR: invalid input syntax for integer: ""

Hi all,
I get invalid input syntax when UPDATEing my radacct table:

freedsl=# \d radacct
                                             Table "public.radacct"
         Column        |           Type           |                          Modifiers
----------------------+--------------------------+-------------------------------------------------------------
  radacctid            | bigint                   | not null default nextval('radacct_radacctid_seq'::regclass)
  acctsessionid        | character varying(32)    | not null
  acctuniqueid         | character varying(32)    | not null
  username             | character varying(253)   |
  groupname            | character varying(253)   |
  realm                | character varying(64)    |
  nasipaddress         | inet                     | not null
  nasportid            | character varying(15)    |
  nasporttype          | character varying(32)    |
  acctstarttime        | timestamp with time zone |
  acctstoptime         | timestamp with time zone |
  acctsessiontime      | bigint                   |
  acctauthentic        | character varying(32)    |
  connectinfo_start    | character varying(50)    |
  connectinfo_stop     | character varying(50)    |
  acctinputoctets      | bigint                   |
  acctoutputoctets     | bigint                   |
  calledstationid      | character varying(50)    |
  callingstationid     | character varying(50)    |
  acctterminatecause   | character varying(32)    |
  servicetype          | character varying(32)    |
  xascendsessionsvrkey | character varying(10)    |
  framedprotocol       | character varying(32)    |
  framedipaddress      | inet                     |
  acctstartdelay       | integer                  |
  acctstopdelay        | integer                  |
Indexes:
     "radacct_pkey" PRIMARY KEY, btree (radacctid)

The query is:


UPDATE radacct
  SET
   AcctStopTime = ('2009-09-25 10:35:44'::timestamp - '0'::interval),
   AcctSessionTime = CASE WHEN '' = '' THEN   (EXTRACT(EPOCH FROM ('2009-09-25 10:35:44'::TIMESTAMP WITH TIME ZONE -
AcctStartTime::TIMESTAMPWITH TIME ZONE   - '0'::INTERVAL)))::BIGINT ELSE '' END, 
   AcctInputOctets = (('0'::bigint << 32) + '0'::bigint),
   AcctOutputOctets = (('0'::bigint << 32) + '0'::bigint),
   AcctTerminateCause = '',
   AcctStopDelay = 0,
   FramedIPAddress = NULLIF('', '')::inet,
   ConnectInfo_stop = ''
  WHERE AcctSessionId = ''
   AND UserName = 'mihamina'
   AND NASIPAddress = '0.0.0.0'
   AND AcctStopTime IS NULL




I cannot find the problem....
Any hints?
Thank you.

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