Map shows old location after traveling via Nether

When I enter the Nether holding a nonblank map and then return to the Overworld, the map shows me as being in the position from which I entered the Nether, even if I've landed in a different portal. In single-player mode, when I exit to title and reload, the map shows my updated position, so this is a workaround (not sure it'd work in multiplayer though).