Im using mac os x 10.8.3

with safari 6.0.4 (8536.29.13)

And one more thing 

a reg for one reason

cood you add to  http://api.jquery.com/animate/

margin info (marginLeft, marginTop, marginRight, marginBottom)

i forgetting sometimes about this and it will be very nice if you write about this on animate page

tnk for reading and good luck