You can do this:
<tmpl_var name="mybody" escape="none">
In your vlibIni.php file, there's an Option called DEFAULT_ESCAPE.
By default, this is set to html, which is helpful as you don't have to escape your vars on every tag (like above)... vlibTemplate will do it automatically.
To see what options are available, go to the OPTIONS section of the vlibTemplate doc.
Kind regards,
Kelvin