outputting braces when there not a patTemplate var

[ichilver]

I need to output braces as part of the file.

Example of template

<pattemplate:tmpl name="page">
  // Some stuff here   
  options {   
   listen-on { {LISTEN_ON} };   
  };   
  // Some stuff here   
</pattemplate:tmpl>  

I need the output to look like

  // Some stuff here
  options {
   listen-on { 10.10.10.1,10.10.10.2 };
  };
  // Some stuff here

However what I actually get is

  // Some stuff here
  options {
   listen-on ;
  };
  // Some stuff here

As you can see I get some of the curly braces but others.

I tried changing the line in the template

<pattemplate:tmpl name="page">   
  // Some stuff here   
  options {   
   listen-on { <patTemplate:var name="LISTEN_ON"/> };   
  };   
  // Some stuff here   
</pattemplate:tmpl>   

But still the same result.

I tried doing { and } on the braces I needed but nothing.

Ideas?