Since buying a BDP-S490 it has been unable to play anything, since the ESonyBDP quirks aren't supported by the player.
It appears that modern Sony Blu-ray firmware works without quirks; the patch at  fixes it perfectly for me.
Unfortunately I can't find a more general solution, because the new and the old (BDP-S373) identify themselves in exactly the same way:
Date: Wed, 02 Jan 2013 19:29:41 GMT
X-AV-Physical-Unit-Info: pa="Blu-ray Disc Player";
X-AV-Client-Info: av=5.0; cn="Sony Corporation"; mn="Blu-ray Disc Player"; mv="2.0";
Perhaps a config file option?