The market for travel-management software continues to heat up. Oracle Corp. recently acquired E-Travel Inc., a provider of online corporate travel-management systems. The company's E-Travel System allows a company's employees to book travel using a Web browser. The decision by the Redwood Shores, Calif.-based database and applications software giant reflects a growing trend in which more companies are putting travel management online to speed planning as well as expense filing and approval. Oracle's eTravel product, to be integrated with its travel reimbursement application, Oracle Self-Service Expenses, will go up against a host of leading software vendors in the travel and entertainment automation market. Among them are Concur Technologies Inc., Redmond Wash.; Captura Software Inc., Bothell, Wash., Extensity Inc., Emeryville, Calif.; Necho Systems Corp. of Mississauga, Ont.; and Value Integrated Network Inc., Barrington, Ill.