try accessing the imported contacts via the 'People'
if they have a number stored the text option should come ! :)
if you had accessed the contacts via the dialer then the sms option doesnt come ! :)
also
scroll the last on this thread
http://answers.microsoft.com/en-us/w...a-461a66294360
"
Work phone is not considered a mobile phone, hence why it isn't offered in messaging. You can create as many contacts for each person as you like... Each with his own mobile number. There are ways to do it."