JMSMessenger is a Java application you can download to your mobile. You can acess to your MSN Messenger account, sending messages to your contact list, whether they're at their computer or on their mobile (the last just in case they have installed MOVILMessenger).
The service is compatible with a wide range of mobile phones with an Internet conection through GPRS, UMTS or EDGE (Nokia, Siemens, Motorola, Sony-Ericsson, etc.), and it is independent of your company operator (Vodafone, BT, Orange, T-online, etc)
You have an option to download the application for free. Besides, you can connect as many times as you want for 10 minutes without any cost. After that, the application will ask you for a code to subscribe to MOVILMessenger.