Problems with QueryCoordSource and query modes

[sdlime]

We need to know the real mode (ala map) before mucking with setting 
QueryCoordSource. For example in query mode mapext should have no effect, it 
does now though. This report based on the following email:

Hi Steve. I'm sorry to boring you with this question, but... it doesn't go:

http://laplace/mapserver/mapserv.exe? 
map=calabria/calabria.map
&mapext=2611685.07+4392492.28+2903099.95+4286980.00
&mapsize=1024+370
&layers=limiti_comunali
&mapxy=2646326.95+4362345.91
&mode=querymap

The error is:
mapserv(): Web application error. Query mode needs a point, imgxy and mapxy are 
not set.

If i remove "mapext" the query run fine. But, of course, return me the entire 
map...

Where is the problem?

Thanks a lot,
Alessandro.