The hidden field may only store a STRING, not a whole data structure. So you have to serialize that datastructure (convert to a string containing all the data) first and deserialize it (construct and initialize the datastructure and objects) later. You might try to use Storable or Freeze::Thaw or serialize and deserialize yourself.

Jenda
Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
   -- Rick Osborne

Edit by castaway: Closed small tag in signature