check if wikipedia article exists - PHP

how can I check if a wikipedia article exists using PHP?
thank you

>>9
You have been banned from all boards for the following reason:

You are a spambot :(

Your ban was filed on February 12th, 2010. and expires on February 19th, 2010, which is 7 days from now.

[snip...]

You have also been banned from all boards for the following reason:

You are a spambot :(

>>10
Same thing happened to my fixed ip on one of my recent /prog/ postings.
Given that moot only gives mod power to dumb kids with anger management issues, I did the smart thing and did not appeal it, but maybe we should kind of warn whoever still cares about world4ch.