No there isn't any support for that. It is possible.
tk2dTextGeomGen.SetTextMeshGeom sets the geometry
This line -
cursorX += (chr.advance + data.spacing) * data.scale.x;
moves the cursor forward. If you can evaluate positions on your curve, you can pass that into cursorX and cursorY to move it in any way you like. If you want it to reorient glyphs to the tangent thats possible too. All the geometry generation happens in that one function.