Adjusted some fine details.

src/smtp.lua

@@ -87,7 +87,7 @@ end
 local function sendsource(mesgt)
     -- set content-type if user didn't override
     if not mesgt.headers or not mesgt.headers["content-type"] then
-        coroutine.yield('content-type: text/plain; charset="iso-88591"\r\n')
+        coroutine.yield('content-type: text/plain; charset="iso-8859-1"\r\n')
     end
     -- finish headers
     coroutine.yield("\r\n")
@@ -104,7 +104,7 @@ end
 local function sendstring(mesgt)
     -- set content-type if user didn't override
     if not mesgt.headers or not mesgt.headers["content-type"] then
-        coroutine.yield('content-type: text/plain; charset="iso-88591"\r\n')
+        coroutine.yield('content-type: text/plain; charset="iso-8859-1"\r\n')
     end
     -- finish headers
     coroutine.yield("\r\n")
@@ -135,7 +135,7 @@ local function adjustheaders(mesgt)
     mesgt.headers = mesgt.headers or {}
     mesgt.headers["mime-version"] = "1.0" 
     mesgt.headers["date"] = mesgt.headers["date"] or 
-        os.date("%a, %d %b %Y %H:%M:%S") .. (mesgt.zone or ZONE)
+        os.date("!%a, %d %b %Y %H:%M:%S ") .. (mesgt.zone or ZONE)
     mesgt.headers["x-mailer"] = mesgt.headers["x-mailer"] or socket.version
 end
 

test/testmesg.lua

@@ -0,0 +1,53 @@
+mesgt = {
+    headers = {
+       to = "D Burgess <db@werx4.com>",
+       subject = "Looking good! (please check headers)"
+    },
+    body = {
+        preamble = "Some attatched stuff",
+        [1] = {
+            body = "Testing stuffing.\r\n.\r\nGot you.\r\n.Hehehe.\r\n"
+        },
+        [2] = {
+            headers = {
+                ["content-type"] = 'application/octet-stream; name="luasocket"',
+                ["content-disposition"] = 'attachment; filename="luasocket"',
+                ["content-transfer-encoding"] = "BASE64"
+            },
+            body = ltn12.source.chain(
+                ltn12.source.file(io.open("luasocket", "rb")),
+                ltn12.filter.chain(
+                    mime.encode("base64"),
+                    mime.wrap()
+                )
+            )
+        },
+        [3] = {
+            headers = {
+                ["content-type"] = 'text/plain; name="testmesg.lua"',
+                ["content-disposition"] = 'attachment; filename="testmesg.lua"',
+                ["content-transfer-encoding"] = "QUOTED-PRINTABLE"
+            },
+            body = ltn12.source.chain(
+                ltn12.source.file(io.open("message.lua", "rb")),
+                ltn12.filter.chain(
+                    mime.normalize(),
+                    mime.encode("quoted-printable"),
+                    mime.wrap("quoted-printable")
+                )
+            )
+        },
+        epilogue = "Done attaching stuff",
+    }
+}
+
+-- sink = ltn12.sink.file(io.stdout)
+-- source = ltn12.source.chain(socket.smtp.message(mesgt), socket.smtp.stuff())
+-- ltn12.pump(source, sink)
+
+print(socket.smtp.send {
+    rcpt = {"<db@werx4.com>", "<diego@cs.princeton.edu>"},
+    from = "<diego@cs.princeton.edu>",
+    source = socket.smtp.message(mesgt),
+    server = "smtp.princeton.edu"
+})