Mapserver as WMS with Mollweide proj

[antonio]

HI list,
I am developing an application using  OpenLayers and Mapserver.I need to 
use Mollweide projection .
If I use Mapserver with this projetion the adjacent tiles don't  match , 
the projection is completely not aligned, the I have to use the untiled 
class in OpenLayers. This, of course, slow down my application and I 
lost the smoothly pan and zoom.
I am absolutely   not able to use Mapserver as WMS server with this 
projection. When I call the WMS the return is always in EPSG:4326. Is 
this probably the OpenLayers fault?

Thanks for your help

Antonio