> I've write the following function inside a dll delphi
>
> << BEGIN FUNCTION >>
>
> function Get_Age(Born,Limit : TDate) : String;

"string" will never work! It's a Delphi type.

You need to use PChar.

Have you tried any of the "how do I write UDFs for Firebird/InterBase"
documents on the web?

Martijn Tonies
Database Workbench - development tool for Firebird and more!
Upscene Productions
http://www.upscene.com
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