If you plan on doing this more in the future,use plastic bottles for lighter weight, it cost me about $12 bucks to ship a six pack of glass bottles a few states away,i used usps but wont again,its a stupid law.Use fed ex and if they ask just say its glass if it is glass.
Dont worry too much a local homebrew club has instructions on shipping it for people that cant make it to meetings to send it,i figure if they can do it why cant i. Not to mention all the trades going on on beer rating sites and even here.
I think usps mentioned something about liquids or anything that could leak,and i shook my head and said glass and its fragile.The movie pet detective when Jim Carey is kicking the box around,comes to mind whenever i ship something that says fragile on it.