Porting to Mac?

I'm developing a front end for a Unix Oracle database and was planning on
using Delphi. However, the client now informs me that the app will need to run
on 6 Power Macs as well.

The question:  anyone know a *good* C/S tool which will allow me to write once
and deploy on both platforms?  The app is quite simple, just some simple Data
entry screens and predefined queries.

Thanks for any help.  Private email is best.