There are couple of solutions out there.
1. mobileMT for Movabletype
http://mobilemt.sourceforge.net/src/
2. Kablog
http://www.kablog.org/
3. Some soultions can be found here for MT:
http://www.movalog.com/archives/plug...ng-with-mt.php
4. Typepad.com:
if you subscribe to typepad, it allows you to moblog. Search for moblog feature to enable it.
Hope this helps!