I'm trying to fetch Wikipedia pages using [LWP::Simple](http://search.cpan.org/dist/libwww-perl), but they're not coming back. This code:

```
#!/usr/bin/perl
use strict;
use LWP::Simple;

print get("http://en.wikipedia.org/wiki/Stack_overflow");

```

doesn't print anything. But if I use some other webpage, say `<http://www.google.com>`, it works fine. 

Is there some other name that I should be using to refer to Wikipedia pages? 

What could be going on here?