[Zope] how to add a DTML Page to a specific folder

[IDEA WS]

Here is a script that adds a new DTML page with a name from the form input
field and generates a new folder with 'NewFolder' id and title.

Could anybody suggest me how to add a new DTML Documentt this way (with a
form) but to a specific, already existing folder.
Or how to create a folder and a document placed in there with the same form,
making it possible to specify the titles, but automatically generate
different default  ids for these objects.

---------------------------------------------
<!--#with pages-->
<!--#if expr="_.has_key('AddPage')"-->
  <!--#call expr="manage_addDTMLDocument(NewPage, NewPage)"-->
  <!--#with expr="_[NewPage]"-->
       <!--#call expr="manage_addFolder('NewFolder', 'NewFolder')"-->
   <!--#/with-->
<!--#/if-->
<FORM>New Page:
<INPUT TYPE="TEXT" NAME="NewPage"><BR>
<INPUT TYPE="SUBMIT" NAME="AddPage" VALUE="Add page"></FORM>
<!--#/with-->
---------------------------------------------

Thanx
Lena