JAVOX provides a mechanism for the development of spoken-language systems from existing desktop applications. We present an architecture that allows existing Java 1 programs to be speech-enabled with no source-code modification, through the use of reflection and automatic modification to the application's compiled code. The grammars used in JAvox are based on the Java Speech Grammar Format (JSGF); JAVOX grammars have an additional semantic component based on our JAVOX Scripting Language (JSL). JAVOX has been successfully demonstrated on real-world applications.