Maximum Length for String Parameters

Hello all,

I am using Oracle 8.1.7 and Delphi 5 Ent. I have an Oracle Store
Procedure which return data of varchar2 type. This procedure have been
tested in SQL plus and worked fine.

When I call this Procedure in delphi, if the returning data is less than
255 characters, it works. But, more than that, it return the error
"General SQL error ORA:06502:PL/SQL:numeric or value error."

The data type of the result parameter of the Store Procedure is ftString
type. But it seems that the result parameter can't accept characters
with length larger than 255.

Does anyone know how to solve it ?