OSPF MD5 authentication errors in 5.0beta2

I am having MD5 authentication errors on 5.0beta2. I have three homegrown portwell-based routers on 5.0beta2 and have seen frequent MD5 errors like this:

Discarding MD5 packet: authentication failed
Invalid sequence number

Assuming I have my OSPF MD5 settings correct, is this driven by the version of ROS? Is there a safe upgrade for OSPF from ROS 5.0beta2?

5.0beta2 was one of the first version of v5.x (it is more than half year old), it is strongly suggested to use newer version.

On RC7, MD5 authentication works perfectly.