Update: It seems indeed that I was misinterpreting information I had, and SO is doing the right thing.
I have a myopenid account (nathansamson.myopenid.com)
I also have a redirection on my website (quite recently), so I can type nathansamson.be
<link rel="openid.server" href="http://www.myopenid.com/server" /> <link rel="openid.delegate" href="http://nathansamson.myopenid.com/" />
I have an (openID) account on stackoverflow, created with nathansamson.myopenid.com.
When I now tried to log onto Stack Overflow with nathansamson.be, it tried to automatically create a new account, instead of logging in with my old account. This is
A bug in OpenID handling on overflow websites (you shouldn't look at the input, but at the claimed_id (these are the same for nathansamson.be and nathansamson.myopenid.com)
Can you merge this accounts? Now I have 2 accounts on Stack Overflow.