Why a mesh does not behave as a united surface?

Hello

I have a mesh with a material applied in all surface. The material is airport of the  roadway_signs.pal palette.

If i divide the mesh then i have more polygons in the mesh, but now the mesh not is a continuos surface. Each polygon is the new surface.

The material is repeated in each polygon of the mesh. The material not is one for all the mesh.

See image

If I convert the sphere in a mesh is the same problem.

See image

Then, how can I have more polygons in the mesh and only one image of the material, in this case, of the airplane in the mesh?

Thank you

Joaquín

Aecosim 08.11.09.750_es