IBM announced that it has signed a pact with Ariba, under which that company’s software for tracking spending will become available in the cloud via IBM’s Lotus subsidiary. Earlier this month, IBM acquired Cast Iron Software to gain access to middleware for integrating cloud computing services. And prior to that, IBM’s Cognos, Websphere, DB2 and Rational software offerings have all been made available via the cloud. According to Beverly Dewitt, program director for IBM’s LotusLive partner program, there’s nothing random about the IBM cloud computing strategy. Under the auspices of the LotusLive cloud computing platform, IBM is inviting application vendors that address specific business processes, such as spend management in the case of Ariba, to become full-fledged LotusLive partners alongside vendors such as Skype and Salesforce.com.