Microsoft and the Symbian alliance are deadly rivals, but the evidence that sooner or later (probably sooner) they're going to have to work together is becoming compelling. The latest signpost is a mobile data alliance between Microsoft and NTT DoCoMo which is due to kick off later this month, according to Japanese reports. The interesting connection here is that DoCoMo, the mobile communications arm of Japanese giant NTT, is a development partner with Symbian and intends to ship an EPOC-based Communicator device next year. So by teaming up with Microsoft DoCoMo seems to be building a bridge between the Symbian camp and Redmond. Microsoft's mobile data deals so far have involved CE-based client devices and Microsoft BackOffice apps, whereas in this case it looks like it'll be Symbian devices and BackOffice apps. This could turn out to be part of the breakthrough that nearly happened last week when, according to reliable sources, Microsoft ducked out of the Ericsson-led GPRS Applications Alliance at the last minute. Microsoft still won't have joined in with the others via the DoCoMo deal, but it should at least have offered tacit recognition that by pushing the CE-client/MS-server combination it risks losing the back end as well as the client. The DoCoMo deal will be a 50-50 venture, and seems to be specifically back end. It's intended to set up a database centre where mobile users' personal information will be stored. ®