When a contract tries to send ether using msg.sender.send() to a contract-based wallet it fails (without error). However, msg.sender.send() works if the sender is the etherbase account. A workaround I found was to use tx.origin.send() but this then sends the amount to the etherbase account and not to the calling wallet.

Shouldn't msg.sender.send() do its job no matter where the address points (contract or account)?