[GRASSLIST:2775] v.patch/merge ?

Hello,
I have a set of four vector maps (map.$x), each corresponding to a quad. I
want to create a new vector map (map.0), encompassing the four ones.
I first reclassed each quadmap, making sure that areas that shared the same
labels have the same category, whatever the map. Then, I ran
"v.patch i=map.1,map.2,map.3,map.4 o=map.0"
I have a problem with the areas at the quads interface: during v.support,
these areas are considered as opened (when they don't look like it when
interrogated with d.what.vect on each quadmap), and it seems they can't be
patched. Please have a look on the zoomed picture enclosed:
map 1: areas are in white, lines in red
map 2: areas are in grey, lines in yellow (note the border line, shared by
map1 and 2)
map 0: areas are in blue.
The areas both side of the border line have the same categories.

Any idea/comment/workaround especially welcomed.
Thanks in advance
P.

--
Soil & Water Laboratory
Dept. of Biological & Environmental Engineering
Cornell University
ITHACA, NY 14853
Tel: (607)255.2463

(attachments)

areas.png