Official errata for the the D&D v.3.0 book Oriental Adventures can be found in the following archive on the Wizards of the Coast website:
http://archive.wizards.com/default.asp?x=dnd/er/20040125a
No further errata or comments.
v.3.5 Update
An official (but not 100% comprehensive) update of Oriental Adventures to the v.3.5 rules can be found in Dragon Magazine #318 (April 2004), pp. 32-48. Unofficial errata for that update follows:
p. 45, Mamono: This monster's type was Shapechanger in v.3.0, but that is now a subtype in v.3.5. No new type is given in Dragon Magazine, but Aberration seems to be most appropriate.
p. 45, Naga, Shinomen, Greensnake: Of all the Shinomen naga varieties, this one was not changed to Monstrous Humanoid. Either that is an error and it should be Monstrous Humanoid, or it remains a Humanoid because it is the only Shinomen naga of Medium size. (Humanoids cannot be Large.)