There are a *lot* of reasons why it would run correctly from the command line, but not run from your browser. Did you look in your server's error log? You should have an error message in there.

Are the permissions set correctly? They should be 0755 so that the web server can execute your script.

Did you output a content header?

print "Content-Type: text/html\n\n";
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Read the Idiot's Guide.