Same age as their parents?
The scenes where you see Iphicles and his mother together seem completely wrong. They look exactly the same age, they made absolutely no attempt to make her look older than she is. The same goes for King Amphitryon, he doesn't look old enough to be the father of Iphicles.
I found it to be a fairly major flaw and made it a lot harder to suspend disbelief and just enjoy the movie.
That and the fact that Herculese makes whale noises and weird animal groaning noises whenever he gets into a fight. He's part god, not part goat.