1. A method for processing of message data from messages sent between a first application recognizing messages of a first format and a second application recognizing messages of a second format but not the first format, the method comprising: selecting a document type definition (DTD) file using a first graphical user interface (GUI), wherein the DTD file comprises components relating to XML message tags; creating a first integration object using a second GUI, wherein said first integration object comprises a first set of components selected from the components of the DTD file, said first set of components relate to tags that are contained in a message header of a standardized XML request, creating a second integration object using a third GUI, wherein said second integration object comprises a second set of components selected from the components of the DTD file, said second set of components relate to tags that are contained in a transactional portion of the standardized XML request, creating a third integration object using a fourth GUI, wherein said third integration object comprises a third set of components selected from the components of the DTD file, said third set of components relate to tags that are contained in a transactional portion of a standardized XML response message; a computer system receiving an XML message from the second application; the computer system replacing first tags in the received XML message with the first components, respectively, of the first integration object; the computer system replacing second tags in the received XML message with second components, respectively, of the second integration object; modifying one or more of the first components of the first integration object without modifying the second and third integration objects; the computer system receiving a second XML message from the second application; the computer system replacing first tags in the received second XML message with first components, respectively, of the modified first integration object; the computer system replacing second tags in the received second XML message with second components, respectively, of the second integration object.