meshing of infinitesmaly small dipol on huge cylinder in CST

Hi
I am trying to calculate the E FIELD OF VERY small dipole(.4mm) placed over a cylendeir of size x(400mm),y(200mm)z(200mm).Now cst represent my dipole only as a single point.does any body know this representation is enough for correct results or i have to do something else.any help will be highly appreciated.
kindest regards
ali