Question : DFS Replication Alternatives with possible file locking

We are currently using DFS (2003 r2) to replicate data from our two branch offices back to our HQ.  I am looking for an alternative solution that will do the same and possibly add file locking so users in the HQ can access branch office data stored in the HQ, yet that data becomes locked in the branch office.  Any suggestions?

Answer : DFS Replication Alternatives with possible file locking

Well if you're looking for a packaged solution that you can buy, I'd recommend checking out Globalscape's WAFS.

DoubleTake, SureSync, and Symantec Replication Exec also handle replication, though I don't know that they'll lock the files as you are requesting.