1. Computer-readable media embodying instructions executable by a computer to perform a method comprising: providing a Java developer kit class library comprising a plurality of first Java classes; providing a Java Open Foundation class library comprising a plurality of second Java classes each containing one or more of the first Java classes; providing a .NET software developer kit class library comprising a plurality of .NET classes; providing a .NET language Open Foundation class library comprising a plurality of first .NET language classes each containing one or more of the .NET classes; wherein each of the .NET language classes presents the same method signature as one of the second Java classes; receiving Java source code defining third Java classes, one or more first calls to one or more of the first Java classes, and one or more second calls to one or more of the second Java classes; translating the third Java classes into second .NET language classes; and translating the first calls to calls into the .NET software developer kit class library without modifying the second calls.