As I can't believe that nobody else did an upgrade Squeeze to Wheezy and obviously re missing feedback did not run into the smbd issue, may I ask you to share your upgrade procedure with us, please!?
Well, I intend to upgrade over the next few days, so will let you know how I fare with this.
Assuming I can locate a "known to work" new uBoot that seems to be required. For some reason Marvell has not published anything on the downloads area of this site.