I dont really see anything wrong with it, if they're sentient, similar to us and mate in the same way as us then I dont see an issue, although of course many people would.
Also I really do not understand all the people saying its bestial, if they are sentient and intelligent then its not like 'screwin' a pooch', its something completely different.
I mean, if you find someone you like...REALLY like then should you be denied being able to...be with them just because of...differences?
I'd pretty much liken a member of an intelligent race to another human person anyday.
...notice how I said 'an' intelligent race rather than 'another' : D.