Sony Ericsson W850i Quick Start Manual page 14

Messaging 2
5. Send the message
Press Continue. To send to a mobile > Enter phone no.. To send
to an email address > Enter E-mail addr.. To use a number or
email address from your phonebook > Contacts lookup.
Then press Send.
Note: if you're sending the message to a person whose mobile isn't
MMS compatible, they'll be sent a web address to view it on.
To send your message to more than one person, press More > Add
recipient and add more mobile numbers or email addresses.
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