XSLT Error

Empty filename at /home/ubuntu/perl5/perlbrew/perls/perl-5.18.0/lib/site_perl/5.18.0/Chameleon5/Template/XSLT.pm line 575.

Response XML

<?xml version="1.0"?>
<response>
  <form method="post" uri="" key="login" uuid="F0F234BC-851C-11F1-8696-A34A7BD1CDC2" encoding="&#x2713;">
    <field value="" name="username" key="username" display="Username" widget="text" id="uuid-F0F268D8-851C-11F1-8696-A34A7BD1CDC2" attrs=""/>
    <field id="uuid-F0F2B054-851C-11F1-8696-A34A7BD1CDC2" attrs="" display="Password" widget="password" name="password" key="password"/>
    <field widget="submit" display="Login" id="uuid-F0F2F8E8-851C-11F1-8696-A34A7BD1CDC2" attrs="" value="" name="submit" key="submit"/>
  </form>
</response>