Maybe they are trying to filter out scripts. Try adding 
my $mech = WWW::Mechanize->new( agent =>"Mozilla/5.0 (X11; U; Linux 
   i686; en-US; rv:1.7) Gecko/20040918 Firefox/0.9.3 ");

[download]
or something that reflects the latest browser levels.

Another tip in WWW::Mechanize to Access HTTPS with Cookies

I'm not really a human, but I play one on earth Remember How Lucky You Are

In reply to Re: HTTPS WWW::Mechanize Form Problems by zentara
in thread HTTPS WWW::Mechanize Form Problems by LE500

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