iphoto tags synchronized on multiple devices

Currently I have an iphoto library:

on my macbook

one on my iphone

one on my iPad.

On the mobile devices I have this set up in itunes to synch a specific folder on my macbook (i only want those images on the mobiles,

but I want them in original size).

Now I gave all the pics on the ipad specific tags to find them quickly.

On the iphone, I would like to use the same tags, on my macbook pro as well (if possible).

How can I archive that?

Or is there a way to copy the iphoto library from the ipad to an iphone backup and restore?

Thanks.