Who can help me? (DBLink)

I am connect from a Oracle 7.3.2 to Oracle 8.1.5 , and the 8.1.5 also connect to another oracle 8.0.5;
I execute some procedure on 7.3.2 , I can execute it with debug mode ; but when in working mode , I get the error 'ora-02068'; My Procedure write in 8.1.5,which between the 7.3.2 and 8.0.5. I use the dblink . The dblink had run normal five month , but now it can't work. Help Me!

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Since the database in the 8.0.5 rebuilt , I modified my dblink define ,I can access other object through the dblink ,even I can execute my procedure with SQL*Plus correctly . Now I found new msg: 'ora-02062',sometimes it appear. If I drop the dblink and restart the Oracle service in 8.1.5(the middle of 7.3.2 and 8.0.5), my procedure can work a short time then it return with others exception. Who can tell me why and how to do with this?

could you post the ORA-2068 error message. One of the suggestions is drop the link and recreate it. But before doing so, could upi pl. let us know the OS and the error string that you get to get an idea of what is causing. The ora-2068 is a server error and should have given you some message.

Sam