Ooops - that had a tiny little bug I had repaired on my installation but not in the released version. This is now repaired and it should now work as expected.
End of line 163 in dLetter/send+receive/rec_send.py
needed a colon ':'
Additionally little design issue has been improved, though this is not crucial.
Funny enough, no one complained, though it has been downloaded a few times. I hope you do not despair and think it is a wrong configuration of your client
Sorry for any inconvinience.
Simply redownload and overwrite your installation. If you already have done some customizing, only overwrite the dLetter/send+receive/rec_send.py