From IMFreedom Wiki

In the MSN protocol, notifications are the primary means of receiving MSN Mobile messages. They are received with the IPG command and are in the XML format as follows.

<NOTIFICATION id="Number (Message Counter?)" siteid="111100400" siteurl="">
	<TO name="Email Address">
		<VIA agent="mobile"/>
	<FROM name="tel:+Mobile Phone Number|Email Address"/>
	<MSG pri="1" id="1|407">
		<CAT Id="110110001"/>
		<ACTION url="2wayIM.asp"/>
		<SUBSCR url="2wayIM.asp"/>
		<BODY lcid="1033">
			<TEXT>Message Text</TEXT>
  • The name attribute of the FROM tag may contain either a mobile phone number with the prefix "tel:+" or an email address, depending on whether the sender has their mobile phone set up with MSN Mobile or not.
  • The id attribute of the MSG tag is a 1 if it is a normal message, but a 407 indicates that the message you just sent was too long for the mobile device and the TEXT tag is then empty.