Map Tiles Improperly Aligned for OpenLayers - Clue Request

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Map Tiles Improperly Aligned for OpenLayers - Clue Request

Hello Everyone,

I used TileCache, Mapserver, and the GSHHS shapefiles to create seven levels of tiles for OpenLayers using EPSG:3995.

The map projection appears to be correct, and the tiles display properly in OpenLayers.  However, there's a problem.  The map is not centered properly.  The North Pole has been moved over Greenland.

You can see the problem in this image:

Off Center Map

Note that the graticule works poorly in this projection.  This is a known issue with OL, but it is useful in showing that the map center is not aligned properly.

I have looked at many previous postings related to TileCache and OpenLayers, but I have not seen this particular problem described before.  

This is the second of two tile sets that we have created for this project.  The first one was for the default OpenLayers projection EPSG:4326, and it did not require any particular configuration to be aligned correctly.

At this point, we are not certain whether this off-center map is the result of the tile set being built incorrectly (i.e. mapserver or tilecache), or whether it is being loaded incorrectly by OpenLayers.  I have not found a way to change the way that a tile set is aligned in OpenLayers so far.

Does anyone recognize this problem, and can you give me an idea of how to go about correcting it?
I really appreciate your help.

  Scott C. in Cary, NC USA