I think I figured it out, for anyone who might stumble across this post in the future. It looks like you need to add the shared keyword to the tunnel protection command. ie... interface tunnel 0 ... tunnel protection ipsec profile MyProfile sharedend...
wellu - Did you ever find a solution to this problem? I'm experiencing the same issue on a new implementation. This is the first thing I've found so far that describes the exact problem I have.