  We propose an alternative scenario for the generation of entanglement between
rotational quantum states of two polar molecules. This entanglement arises from
dipole-dipole interaction, and is controlled by a sequence of laser pulses
simultaneously exciting both molecules. We study the efficiency of the process,
and discuss possible experimental implementations with cold molecules trapped
in optical lattices or in solid matrices. Finally, various entanglement
detection procedures are presented, and their suitability for these two
physical situations is analyzed.
