I feel that anyone who has faith in Guruvayurappan should be permitted into the temple, even if he has been born into some other religion. Now the question is how to separate the faithful from the "tourists", who are there to see the temple, and anyone who is out to create trouble(the temple is suffocatingly crowded anyways, so we dont want any extra people :-) ) Anyone who by his own admission is a bhakta of Guruvayurappan should be permitted to enter. We cant have all people entering the temple signing declaration vowing their allegiance to him.
So how about this ... Anyone how has to enter the temple has to hold his hands above his head and cry out "GURUVAYURAPPAAAAAA" before entering the temple .. :-)