Killed sessions remain in DB

[efrijters]

Hello guys,

I executed the statement below and I saw that a lot of killed sessions remain in the db. How can I release those connections?

select username,sid,serial#,logon_time,status 
from v$session
where status<>'ACTIVE' and logon_time < trunc(sysdate)
order by logon_time

USERNAME                           SID    SERIAL# LOGON_TI STATUS
--------------------------- ---------- ---------- -------- --------
SYS                                 13       1412 25-08-03 KILLED
SYS                                 39      57241 27-08-03 KILLED
SYSTEM                              52       5396 02-09-03 KILLED
SYS                                 38      64062 23-09-03 KILLED
SYS                                 93      33838 23-09-03 KILLED
SYS                                  8      60551 23-09-03 KILLED
SYS                                103       1440 23-09-03 KILLED
SYS                                 73       9639 23-09-03 KILLED
SYS                                 88      63663 24-09-03 KILLED
SYS                                 45      27293 24-09-03 KILLED

Note: We always log off at the end of the day.

The connectsions were killed by " alter system kill session 'SID, SERIAL#';" and I thought, that after a while they would vanish by the work of pmon...

SQLNET.ORA contains:
sqlnet.expire_time = 10


Help is very appreciated.

Erik