Abstract: A method is provided for routing mobile telephone short text messages between different mobile telephone messaging networks, including mobile telephone messaging networks operated by a single carrier (i.e., intra-carrier messaging) or by different carriers (i.e., inter-carrier messaging). The method includes receiving a short text message at a mobile telephone short message gateway operated by a first mobile telephone carrier, the short text message having a destination directory number (DN). The short message gateway determines that the destination directory number (DN) is associated with one of two or more mobile telephone networks. The two or more mobile telephone networks may be operated by the first mobile telephone carrier alone or by the first mobile telephone carrier and another carrier. The short text message is then routed to the appropriate mobile telephone network based upon its destination directory number (DN).

Abstract: Electronic messaging in a one-to-one, one-to-many, or many-to-many messaging session is directed through a short text messaging application. The short text messaging application incorporates a message thread identifier with a message that is sent to a recipient or group of recipients. The message thread identifier may be embedded in the header information of the message, for example, and is associated with the unique user identification code or network address of each recipient. Any reply to such a message is directed to the originating user and any other recipients based upon the message thread identifier.