Replication

[Quoted] ERROR at line 1:

ORA-02051: another session in same transaction failed
ORA-02063: preceding line from DB
ORA-02055: distributed update operation failed; rollback required
ORA-02068: following severe error from DB
ORA-03113: end-of-file on communication channel
ORA-06512: at "SYS.DBMS_SNAPSHOT", line 380
ORA-06512: at "SYS.DBMS_IREFRESH", line 450
ORA-06512: at "SYS.DBMS_REFRESH", line 182
ORA-06512: at line 1

What does it mean?
How solve this problem?
Help me plz.
I have Oracle 8.0.4 server on NT4 and Personal Oracle 8.0.3 on snapshot site on NT4. Received on Tue Jan 04 2000 - 00:00:00 CET