diff --git a/examples/repl/cmdline.rs b/examples/repl/cmdline.rs
index 0e72396d1..cabd0a2ba 100644
--- a/examples/repl/cmdline.rs
+++ b/examples/repl/cmdline.rs
@@ -450,6 +450,7 @@ pub unsafe fn dc_cmdline(context: &Context, line: &str) -> Result<(), failure::E
                  dellocations\n\
                  getlocations [<contact-id>]\n\
                  send <text>\n\
+                 send-garbage\n\
                  sendimage <file> [<text>]\n\
                  sendfile <file>\n\
                  draft [<text>]\n\
@@ -948,6 +949,16 @@ pub unsafe fn dc_cmdline(context: &Context, line: &str) -> Result<(), failure::E
                 bail!("Sending failed.");
             }
         }
+        "send-garbage" => {
+            ensure!(!sel_chat.is_null(), "No chat selected.");
+            let msg = b"\xff\x00"; // NUL-terminated C-string, that is malformed utf-8
+            if 0 != dc_send_text_msg(context, dc_chat_get_id(sel_chat), msg.as_ptr().cast()) {
+                println!("Malformed utf-8 succesfully send. Not nice.");
+            } else {
+                bail!("Garbage sending failed, as expected.");
+            }
+
+        }
         "sendempty" => {
             ensure!(!sel_chat.is_null(), "No chat selected.");
             if 0 != dc_send_text_msg(
diff --git a/examples/repl/main.rs b/examples/repl/main.rs
index 28f923c3f..7cc700af8 100644
--- a/examples/repl/main.rs
+++ b/examples/repl/main.rs
@@ -3,6 +3,7 @@
 //!
 //! Usage:  cargo run --example repl --release -- <databasefile>
 //! All further options can be set using the set-command (type ? for help).
+#![feature(ptr_cast)]
 
 #[macro_use]
 extern crate deltachat;
@@ -290,7 +291,7 @@ const DB_COMMANDS: [&'static str; 11] = [
     "housekeeping",
 ];
 
-const CHAT_COMMANDS: [&'static str; 24] = [
+const CHAT_COMMANDS: [&'static str; 25] = [
     "listchats",
     "listarchived",
     "chat",
@@ -308,6 +309,7 @@ const CHAT_COMMANDS: [&'static str; 24] = [
     "dellocations",
     "getlocations",
     "send",
+    "send-garbage",
     "sendimage",
     "sendfile",
     "draft",