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 uri="" method="post" uuid="4ED9FE48-65B6-11F0-A04D-EE8262E0087B" encoding="&#x2713;" key="login">
    <field value="" name="username" attrs="" id="uuid-4EDA2E9A-65B6-11F0-A04D-EE8262E0087B" widget="text" display="Username" key="username"/>
    <field widget="password" attrs="" id="uuid-4EDA7404-65B6-11F0-A04D-EE8262E0087B" name="password" key="password" display="Password"/>
    <field key="submit" display="Login" widget="submit" name="submit" value="" attrs="" id="uuid-4EDABC8E-65B6-11F0-A04D-EE8262E0087B"/>
  </form>
</response>