Sorry for making you wait so long, but here it is, NDSMail 0.54d!
I've been (and still am) pretty busy, and NDS development is very time-consuming..
The major issue (SSL) is still not fixed, but as the rest is quite stable I thought I'd give you something to play with. It is compiled with the latest Devkit, dswifi and libfat (DLDI), so even owners of the new-wifi-chipset DSLites should be able to use it. It also contains all the changes from the large overhaul of last autumn. Be sure to check out the attachment feature by sending some (preferably small, see below) jpgs to your DS.
I've created tons of unit tests, everything works fine on the pc (the lib is portable), I've even had someone check it with BoundsChecker. The problem only exists when using it on the DS. I have to find a way to run a debugger on the DS.
Also, the JPG lib causes some trouble with larger images, and I can't get hold of the original author.