simple. microsoft has patents which are infringed in some manner or the other by android devices. samsung is now licensing these patents so that they can avoid any future lawsuit from microsoft for their android and hopefully bada devices. htc has a similar deal in place with microsoft. some other smaller players also have signed similar deals with microsoft.
they probably do actually. but the things are not strange here. i bet a lot of companies have similar deals in place for various products that feature patents and technologies owned by other companies. it is just that google did not bother about signing these deals before launching android and now the manufacturers have to sign individual deals with patent owners. i am just waiting for google's acquisition of motorola to get over. it would be interesting to see if google would use their newly owned patents to target microsoft and Apple. they are sitting very quietly right now.