my guess is that if they are packaged to prevent breakage, and yes to contain spilage should a break occure, they will probably pass the shipping requirements..but the import/export requirements may be stricter.
check to see what health papers etc are required..and remember most postal employees dont know what is required. here I have to remind them they have to inspect the package before shipment and the health papers must be attached to the box for shipping, (new york ag & markets rule for shipping fertalized eggs for,hatching) so it is wise to see what your state as well as country requires before deciding on shipping, because a box of eggs delayed in impound will certainly have a negative effect on hatchability, even if the do survive the trip.