In changing world of computerized information systems modeling of business transactions plays an important role. Business transaction can be defined as extended communicative action loop. Using such approach, business processes and new functional requirements may be represented as choreographed sets of extended communicative action loops with established pragmatic and semantic dependencies. In general case, a computerized information system may be of hybrid nature, that is, it may consist of different versions and types of databases. XML streams’ formatting in hybrid information system is discussed in this paper.