[twitter-dev] user ambiguity

[X10]

When retrieving statuses with /statuses/user_timeline/1250.xml there's
an ambiguity. Should Twitter return the tweets for userid=1250 or for
screenname=1250? Matter of fact, if you use this url for retrieving
tweets by screen name, you'r ok unless a user has a numeric screen
name, in which case you get the tweets of another user who happens to
have that particular user id.
It's an interesting way of getting to know other Twitter users, but
I'm not sure it is desired behavior of the system.