No.
They're simply not supported when loading a mesh - however, you can use them in memblock meshes - so if you loaded your mesh then converted to a memblock, you could then colour the verts manually before exporting back to a mesh. You could even save the memblock to save messing about in the actual engine. It would be pretty tricky to set the colours yourself, especially if you were trying to remake a vertice lightmap or something. I use them on my memblock matrices, but a matrice is far easier to colour than a complex mesh.
Froggermon and ESC paid Kevil to make an .X importer for him to combat this very problem in Frogger's and ESC's Roswell Racers competition entry - I don't think they'd want to share the code with everyone, but I assume this is for DarkGT, not a competition entry so it's worth a shot asking Frogger if he'd share it, perhaps you guys could come to some sort of code trade. I'm not 100% sure if the memblock system is ideal for a complex mesh with lots of differenct textures though - a memblock mesh supports only 1 texture, so you might end up having a different mesh for every different texture - might really slow your engine down (esp considering collision detection).
Van-B

I laugh in the face of fate!