spam on the wiki

[John W. Eaton]

I see several spam pages on the wiki:

  
http://www.octave.org/wiki/index.php?title=Breast_Enlargement_Without_Surgery_-_How-to%27s

  http://www.octave.org/wiki/index.php?title=Capresso_Coffee_Machines

  http://www.octave.org/wiki/index.php?title=There%27s_a_answer_why_Ne...

and looking at the log, it seems we are deleting spam pages fairly
often.  I think we are currently using some sort of captcha to try to
prevent spam but it doesn't seem to be working very well.  Is there
something better we can do?

jwe