I have on one of my private sites a problem with dataform text fields named "date" in Listpages order ( i hope this "naming" is not the cause of the non working sort..).
ListPages order="_date desc" with dataform text-field "date" does not work..

The content is like "JJJJ-MM-DD" and is only sorting ascending in the Listpages output!

Examples of my private site:
Tyical page=http://gfom-ogy-bp.wikidot.com/macro-v8-60 , where the order used in Listpages is order="_date desc" - but this does not work!

[[module ListPages category="macro" parent="." order="_date desc" separate="no" perPage="50"]]

Using this live- Template http://gfom-ogy-bp.wikidot.com/macro:_template

====
[[form]]
fields:
  User-name:
    type: text
    label: User-name
  date:
    type: text
    label: Date
    width: 80
    hint: Use the format "YYYY-MM-DD" (e,g. 2010-05-12)
  comment:
    type: wiki
    label: Comment
    width: 80
    height: 3
  filename:
    type: file
    label: Upload Macro-zip file
[[/form]]