Making a stale MFC banking application nimble so that it can be migrated to cloud

Revision 2
Hi,

We have a huge banking application which has different executables(core executbales are the same but every client has some specific requirements so some changes) and hardware for each client, as the clients are increasing the required hardware cost has increased to around 75% of the total cost.

The problem is this application is built using VC++,C++ and Oracle 9i( with around 4-5 million lines of code )

How do we migrate it to a a nible application so that it can be migrated to cloud eventually.

I was thinking of migrating the application to a webserver using java, java stored procedures, oracle and ofcourse a thin client, but again this doesnt look very promising

Please advice

note - main focus is on decreasing the hardware cost and making the application more efficient and scalable