Urgent help - SOS !!!

On a development database instance 10gR2 on Solaris 10, all of a sudden no one can login except SYS or SYSTEM. However if I grant SYSDBA to SCOTT he can login. If I revoke the grant and make SCOTT a normal user then the connect as Scott/Tiger just hangs.  

There is nothing in Alert log or Udump trace files. I checked if somehow the instance had gone into restricted mode but it is not. I shut the database down and restarted but no help. It is not in archivelog mode. I checked the space on the server and it is ok. There are 4 other instances on the same box and they are fine.  

Do you guys have seen anything like this and can u give me any directions as where to start looking ?  

The Database is 10.2.0.1 on Solaris SunFire V240  

Thanks and have a good day.  

Shreeni
(630) 401-2887 (Mobile)
(630) 837-1730 (Home)
 

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