[Exist-open] Modify xquery from document view

[<g.v...@ng...>]

Wolfgang,
Initially the resource is stored as application/xquery (correctly)
but after recall it inside the document view result as application/octet-stream so the save function change  the mime-type.
A solution is to receck the mime-type based on the name of resource before save it.
But I think there is a bug at low level on return the correctly mime-type.

Giulio