pagetree macro breaks template variables...

If the {pagetree} macro is used in a template that contains variables, the save process will fail. During the "insert variables" stage, the space name disappears from the breadcrumb bar and a "page not found" error is returned when creating the page.

Steps to reproduce:

1. Create a global template with the following source:

   This is my @Topic@ page.
   
   h2. Description
   
   {excerpt}
   @Excerpt|textarea(5,10)@
   {excerpt}
   
   h2. Body
   
   write something here.
   
   
   h2. Mood
   
   When I wrote this, I was feeling @Mood|list(edgy,tense,nervous,anxious)@
   
   {pagetree}
   

2. Navigate to a space where you have permission to create pages.
3. Create a page using the template. Note that the breadcrumb bar no longer contains the space name.
4. Whether or not you fill any variables, the page save will fail.

This happens with both page and space templates. Nothing is returned in the logs.