On a slightly different but associated issue, one of the now defunct (not Outlook Express as far as I know) messaging progs used to offer text messaging to mobiles. Early 2000s.
I think it required a modest bit of paid for extra gubbins to make it work. I guess it was a Corporate thing. (Where I worked then we spent a fortune on IT)
I found this useful.
Any reason why Outlook can't do it for Joe Public (non-corporate) without buying one of the things that Google finds for it? Also, the M/S entry on this sent me to sleep.