What are the effects of smoking Cannabis seeds?

[JDreaming]

When SWIM smokes cannabis, he tries not to put any seeds from his supply in when he packs bowls... he knows the seeds contain no THC and are better to remove and not smoke. But occasionally one falls in to a bowl and gets smoked anyway. Recently SWIM was smoking with a friend and a seed snuck its way into the bowl, and SWIM started smoking it regardless. His friend freaked out and started informing him that seeds contain "plant estrogen"! SWIM asked him if a seed could really contain sex hormones capable of effecting a human and what they would do if smoked. He didn't know, but seemed to be far more scared of the seeds than SWIM had been.

What harm do you think smoking cannabis seeds could cause? Somehow I doubt the estrogen content would be great enough to have dramatic, sexually-altering effects, but do you think it could do anything nasty? What chemicals do you think are in the seeds and what do they do to you if smoked?