Hrm, did it on 8i and 8.0.5 and got the same result.

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SQL> select to_number('54.12', '99.99') from dual;

TO_NUMBER('54.12','99.99')
--------------------------
54.12

SQL> c/54.12/,
1* select to_number(',', '99.99') from dual
SQL> /

TO_NUMBER(',','99.99')
----------------------
0

SQL>
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