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="C0A2AE70-753D-11F1-A0B6-76B225D43659" encoding="&#x2713;">
    <field attrs="" name="username" value="" widget="text" id="uuid-C0A2DBF2-753D-11F1-A0B6-76B225D43659" key="username" display="Username"/>
    <field widget="password" id="uuid-C0A321AC-753D-11F1-A0B6-76B225D43659" key="password" display="Password" attrs="" name="password"/>
    <field id="uuid-C0A36CD4-753D-11F1-A0B6-76B225D43659" widget="submit" display="Login" key="submit" attrs="" value="" name="submit"/>
  </form>
</response>