I have tried all the suggestions, but am still getting that same Exception error.
It's not a problem with access, as I can send a blank email from the same database with different code. I want to email an existing document with a "Send" button on an xPage. I don't need to create a new mail memo (although I've tried this also). I can save the email, and it's perfect: the SendTo and all the fields are there! But I get an error on doc.send() or doc.send(address). My code is similar to Steve's, but I don't need to use replaceItemValue, as I'm emailing the document that's open.
I have added saves for the currentDocument and back-end doc object, but still send() throws the error.