Assuming there is no chance of opposite pressure being put on the body and the lens, it should be fine. I have shipped DSLR's many times, and usually seperate the body and lens. Just make sure that the bag you 'drop it into' is going to secure the camera and lens in place, and certainly make sure to have a good 4-5in of padding between the box and bag.
EDIT: This is assuming a relatively short lens, like the 18-70. If it's something longer, say the 70-200mm or such, you'll definately want to seperate the two.