gvfs and mmap()?

["Dan Kegel" <dank kegel com>]

Can one use mmap() with filesystems mounted via gvfs?
http://lists.laptop.org/pipermail/sugar/2008-March/004728.html
and
http://bugs.winehq.org/show_bug.cgi?id=13783
imply that the answer is 'no'.

If so, this is a significant limitation, as at least one version of
Excel seems to use memory mapping to open documents.