A system of processing extensible markup language 'XML' documents for a wireless mobile communication device, comprising: a device receiver of the wireless mobile communication device configured to receive a processed document from a data server, wherein the processed document is generated by transcoding an XML document using a code book; a device code book system comprising a device cache for storing code books, each code book comprising a set of lookup tables that map between XML tags or attributes and their corresponding tokenized equivalents; and a device transcoding system (40, 42) coupled to the device receiver and to the device code book system and configured to parse the processed document, to request the code book from the device code book system, and to transcode the processed document using the code book to recover the XML document, wherein the device code book system is configured to determine whether the code book is stored in the device cache when the code book is requested by the device transcoding system, to provide the code book to the device transcoding system where the code book is stored in the device cache, and to request the code book from the data server, receive the code book from the data server, and provide the code book to the transcoding system where the code book is not stored in the device cache; wherein the data server comprises: a data server receiver configured to receive the code book request from the device code book system, the code book request identifying the requested code book; a data server code book cache storing a plurality of code books, each code book comprising a set of lookup tables that map between XML tags or attributes and their corresponding tokenized equivalents; a data server code book system configured to determine whether the requested code book is stored in the data server code book cache; a data server code book builder configured to generate the requested code book and to store the requested code book in the data server code book cache where the requested code book is not stored in the data server code book cache; and a data server transmitter configured to transmit the requested code book to the device code book system. a device receiver of the wireless mobile communication device configured to receive a processed document from a data server, wherein the processed document is generated by transcoding an XML document using a code book; a device code book system comprising a device cache for storing code books, each code book comprising a set of lookup tables that map between XML tags or attributes and their corresponding tokenized equivalents; and a device transcoding system (40, 42) coupled to the device receiver and to the device code book system and configured to parse the processed document, to request the code book from the device code book system, and to transcode the processed document using the code book to recover the XML document, wherein the device code book system is configured to determine whether the code book is stored in the device cache when the code book is requested by the device transcoding system, to provide the code book to the device transcoding system where the code book is stored in the device cache, and to request the code book from the data server, receive the code book from the data server, and provide the code book to the transcoding system where the code book is not stored in the device cache; a data server receiver configured to receive the code book request from the device code book system, the code book request identifying the requested code book; a data server code book cache storing a plurality of code books, each code book comprising a set of lookup tables that map between XML tags or attributes and their corresponding tokenized equivalents; a data server code book system configured to determine whether the requested code book is stored in the data server code book cache; a data server code book builder configured to generate the requested code book and to store the requested code book in the data server code book cache where the requested code book is not stored in the data server code book cache; and a data server transmitter configured to transmit the requested code book to the device code book system.