In this work, we present a system for categorizing photographs based on the text of their captions. The system has been developed as a part of the system CODI, an e-commerce application for an Spanish news agency. The categorization system makes able to the user the personalization of their information interests, improving search possibilities in the CODI application. Our approach for photograph categorization is based on linear text classifiers and Web mining programs, specially selected due to their suitability for industrial applications. The evaluation of our categorization system has shown that it meets the efficiency and effectiveness requirements of the e-commerce application.