As far as I know, QAD Financial is now written in C#. This new financial module is the result of an software acquisition to replace the old MFGPRO financial module which was not pretty well designed. QAD 2009 EE integrate plug-ins (MFGPRO, Appshell, QAD Fiancial) to embedd any third-part application in the .Net interface.
Technically, since OE 10.2A, prodataset are used to access any Openedge database from any .Net client (no matter the language you use on the client side). I was told by some QAD sales that only new modules will be developped with this framework. However, most of the batch logic with perdure as .p programs server side because they do not have the means to rewrite the whole ERP in one shot. This will be done progressively.
you have an overview of the architecture un the presentation attached.
hope this help