BlackBerry Ltd. said Monday that its BBM instant-messaging service would become available to users of Microsoft Corp.’s Windows Phones and Nokia Corp.’s X smartphones. BlackBerry made the announcement from the Mobile World Congress, happening in Barcelona, Spain, this week. Until making BBM available to users of Apple Inc.’s iPhones and phones running on Google Inc.’s Android software last year, BBM had been available exclusively for use on BlackBerry devices. Last week, Facebook Inc. announced it had reached a deal to pay $19 billion US for WhatsApp Inc., which makes a rival messaging system to BlackBerry. WhatsApp CEO Jan Koum announced during the Mobile World Congress that the company would be introducing voice services on its application some time in the second quarter of this year, according to an Associated Press report.