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 encoding="&#x2713;" uri="" method="post" key="login" uuid="0715F344-4375-11F1-9697-3770A9425785">
    <field value="" name="username" id="uuid-071625D0-4375-11F1-9697-3770A9425785" widget="text" attrs="" key="username" display="Username"/>
    <field name="password" id="uuid-07166C2A-4375-11F1-9697-3770A9425785" widget="password" attrs="" key="password" display="Password"/>
    <field widget="submit" id="uuid-0716B770-4375-11F1-9697-3770A9425785" name="submit" value="" display="Login" key="submit" attrs=""/>
  </form>
</response>