Microsoft Corporation was receiving requests from their early GSM carrier partners in 1999 for integrated support in Windows CE-based PDAs for SMS messaging. At the time, there was very little wireless and SMS expertise at Microsoft. To deliver a finished solution to their customers, they turned to SJMC, Inc. and Access Softek. Working with only minimal interaction with Microsoft's development team, SJMC, Inc. designed the user interface, defined the feature set, and managed the delivery of a finished, tested, and documented extension to the Windows CE Inbox that allowed users to send and receive Short Message Service (SMS) text messages over their GSM mobile phone. It is believed to be the first SMS client for a PDA device that worked with a variety of GSM mobile phones including models from Nokia, Motorola, and Ericsson. The extension seamlessly integrated into the Windows CE Inbox and allowed the user to send messages to other GSM phones or to Internet email addresses.