[OpenLayers-Users] 900913 mismatch?

[Richard Duivenvoorde]

Hi List,

I'm trying to overlay a google map with data from postgis database 
(roads). On larger scale things seem to be ok, but when zoomed in at 
'meters' scale, roads do not match:
http://www.duif.net/900913-mismatch.jpg

Question: has somebody experienced this? Or does somebody have an 
example of perfect matching of two layers?

When I look at the multimap mercator example:
http://www.openlayers.org/dev/examples/multimap-mercator.html
zooming in at for example Amsterdam, The Netherlands, I see about the 
same mismatch??

my code:

  var options = {
       projection: "EPSG:900913",
       units: "m",
       maxResolution: 156543.0339,
       maxExtent: new OpenLayers.Bounds(-20037508, -20037508,
                                           20037508, 20037508.34)
   };
   map = new OpenLayers.Map('map', options);
   var layer = new OpenLayers.Layer.Google( "Google Hybrid", {type: 
G_HYBRID_MAP, 'sphericalMercator': true});
   map.addLayer(layer);

   layer = new OpenLayers.Layer.WMS( "roads", 
'http://localhost/cgi-bin/mapserv.exe?map=test.map&', {layers: 'roads', 
'format':'image/gif', TRANSPARENT:true}, {'buffer': 0, isBaseLayer: 
false, singleTile: true} );

Tried both reprojecting the data in postgis, using
+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 
+k=1.0 +units=m +nadgrids=@null +no_defs
OR
let mapserver reproject the data. Both give about the same shifts...

TIA

Richard Duivenvoorde