PLS-00201 when trying to call ORA_HASH from a function

Question

SQL> select * from v$version;
BANNER
Oracle Database 10g Enterprise Edition Release 10.2.0.2.0 - Prod
PL/SQL Release 10.2.0.2.0 - Production
CORE 10.2.0.2.0 Production
TNS for Solaris: Version 10.2.0.2.0 - Production
NLSRTL Version 10.2.0.2.0 - Production
SQL> select ora_hash('GOOBERS') from dual;
ORA_HASH('GOOBERS')
1552467184
SQL> create or replace function my_hash(x in varchar2) return number is begin return ora_hash(x); end;
2 /
Warning: Function created with compilation errors.
SQL> show errors
Errors for FUNCTION MY_HASH:
LINE/COL ERROR
1/56 PL/SQL: Statement ignored
1/63 PLS-00201: identifier 'ORA_HASH' must be declared
If anyone has some ideas on this it would be great to hear from you. Thanks.

Answer 1

Thanks Maxim & Rakesh, that worked.
It does look like a bug. The return on it's own works with other functions e.g. ASCII etc. but not ORA_HASH.
The select from dual version is painfully slow (e.g. 25 x times) though so I think I'll use dbms_utility.get_hash_value instead for now. I was planning to use that version in 9i anyway as my app still needs to run on 9i - but I was trying to get the ORA_HASH working for 10g as it is incredibly fast.
Will definitely log it though.