Roberto, you can export your translations to .xml files by visiting the package manager, then a package's info page, and clicking the "Internationalization" link there.
I did that to dotlrn-fs, and it indeed created the .xml file. However, after restarting the server, it still won't show the message.
I tried deleting all the message keys for that package in the lang_message_keys table, then restarting the server so it'd grab the new keys, but the key doesn't show up back in lang_message_keys.
Do I need to select "Import from the .xml file"?
-Roberto
P.S.: Is this documented somewhere so I can stop asking silly questions?