alter user identified externally

Hello.

I have not been able to alter users to "identified externally" unless the user has sysdba privilege:

connect NonDba/password
alter user NonDba identified externally ERROR at line 1:
ORA-01031: insufficient privileges

connect Dba/password
alter user NonDba identified externally

works successfully

Is that the restriction that oracle places on who exactly may execute this command (I'm using oracle 10.2)
or is there a way to work around it?

thank you

Gene Gurevich

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