Oracle Database Discussions

Hello,

I know this question might look stupid, but.. I'm curious if it's possible to lock SYS account. I made a trial, logged to database as sysdba and executed:
alter user sys account lock.
When I look into DBA_USERS: select account status from dba_users where username = 'SYS' and I see account is locked. But I can still log into database (even from remote host, so it's not local OS authent, because REMOTE_OS_AUTHENTICATION is set to FALSE).
Is it possible to lock SYS and if not - how does it working? I looked in some documentation, but couln't find anything.

Greets
Aliq.