You may have to implement the sharing method yourself. In other words, if you want to share a variable between two different processes, you may have to implement some method of serializing that variable; then you can store the serialized version in a file or in a database and both processes can have access to it. Managing changes to the variable across the separate processes will be a challenge.

For serializing the data, look into Storable or Data::Dumper.

Perhaps you could use shared memory for this; you might want to check out IPC::SharedCache, which lets you store data in shared memory. It automatically serializes the data for you. Actually, I'd say this is a good place to start looking.