Brad, If I understand your objective correctly, you want mapserver to re-project your layers for you to this custom projection. For that, I think that you should set the projection for each layer to their "source" projection, i.e., the projection that they are currently in. For you MAP, you should set the projection to the destination projection, i.e., the one that you want to re-project into. Mapserver will automatically re-project it for you (I think).
That said, I have only used standard projections to do this, for example, I have combined UTM with decimal degrees in the same map with this approach. I do not know enough to say how you go about setting the custom google projection on your MAP object. HTH, Robert This is kind of hard to explain but what I want to do is use Mapserver to project my data which is in the GDA94 projection as shown below: "# GDA94 / MGA zone 55 <28355> +proj=utm +zone=55 +south +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs <>" to a projection that will be able to be properly merged with Google maps (using OpenLayers) which uses a projection something like the following: "Update 4: Agreement frrom Melita Kennedy and David Burrows that Google Maps and Virtual Earth use spherical equations for the Mercator projection. The correct proj4 settings are: +proj=merc +latts=0 +lon0=0 +k=1.0 +x0=0 +y0=0 +a=6378137.0 +b=6378137.0 +units=m Note this is different than using the ellipsoidal equations which would be:
