Oracle 10g hangs ...earlier running smoothly

In one of our R&D boxes, we have 10g installed on SUSE linux. It was working fine and in use of users for various apps. Yesterday a user reported me that he cant run sqlplus locally and cant get connected from the client either.

I checked the same thing and found it true. Actually whenever I ran the sqlplus, exp, imp, or any binary locally, it gets hang. Same thing happens when I try to connect from client. One thing I saw wierd that the whole ORACLE_BASE directory had the permissions set to 4755, setting the "sharing" bit on. I switched it back to 755 while keeping the "oracle" file permissions to 4755 but still face the same problem. It hangs on sqlplus or any other oracle binary.
Tried relinking all but still no good.
I cant reboot the box right now. My instinct says its something regarding the permissions but not sure what more can I do.

Can anybody help me please? Any input regarding it will be highly appreciated.

Thanks.

Sid

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