simultaneous sync and encryption

I have just found out about Toucan. I see that it can do synchronization and encryption, but can it do both at once. In other words, can I have an encrypted and un-encrypted folder that er being synchronized at given times (both ways)?

In more details: I want to synchronize a folder between several computers, using an online service (in my case, box.net mapped as a drive using webdav). I want to have unencrypted versions on the computers for easy and fast access, but the "syncing medium" should be encrypted. Hope it makes sense..

And if Toucan cannot do it, could you suggest a tool that can - if possible a free and multi-platform (Windows and Linux) one?

Thanks,
Michal

PS: I just found that the question has been asked before and the answer is "no". If this is still the case, could someone at least suggest a way to do this, please?