Double quotes (and possibly other special characters) break the Customize Navigation Menu page (jsTree widget)

To recreate -

• Administer > Customize > Navigation Menu
• Right click on a menu entry and edit title so it includes double quotes - eg. title = Find "Some" Contacts
• Save

The jsTree widget now doesn't load - just see the spinner spinning.
We've had several reports of this recently - mostly I think from non-english sites so I "suspect" that special characters may also trigger this.

http://forum.civicrm.org/index.php/topic,18361.0/topicseen.html