ORA-23308 while DROP_SNAPSHOT_REPOBJECT

Hello,
do somebody know how to drop snapshot. If I run procedure DBMS_REPCAT.DROP_SNAPSHOT_REPOBJECT, it ends with ORA-23308. I'm totally on the end.

snapadmin_at_ihneds>BEGIN
DBMS_REPCAT.DROP_SNAPSHOT_REPOBJECT (
sname => 'SUPER',
oname => 'ARTICLES',
type => 'SNAPSHOT',
drop_objects => TRUE);
END;
/
  2 3 4 5 6 7 8 BEGIN *
ERROR at line 1:

ORA-23308: object SUPER.ARTICLES does not exist or is invalid
ORA-06512: at "SYS.DBMS_SYS_ERROR", line 95
ORA-06512: at "SYS.DBMS_REPCAT_UTL", line 2484
ORA-06512: at "SYS.DBMS_REPCAT_SNA_UTL", line 1684
ORA-06512: at "SYS.DBMS_REPCAT_SNA", line 126
ORA-06512: at "SYS.DBMS_REPCAT", line 1107
ORA-06512: at line 2

Elapsed: 00:00:00.00

But it exists:
snapadmin_at_ihneds>select count(*) from super.articles;

  COUNT(*)

    321192

I have dropped a lot of snapshots but only this make me problems...

Thank you for any idea,

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Jan Vondrak - PHP Programmer, Oracle DBA
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