diff --git a/bootstrap/venv.sh b/bootstrap/venv.sh
index ce31e6703..6ca082446 100755
--- a/bootstrap/venv.sh
+++ b/bootstrap/venv.sh
@@ -25,9 +25,9 @@ pip install -U letsencrypt letsencrypt-apache # letsencrypt-nginx
 echo
 echo "Congratulations, Let's Encrypt has been successfully installed/updated!"
 echo
-echo -n "Your prompt should now be prepended with ($VENV_NAME). Next "
-echo -n "time, if the prompt is different, 'source' this script again "
-echo -n "before running 'letsencrypt'."
+printf "%s" "Your prompt should now be prepended with ($VENV_NAME). Next "
+printf "time, if the prompt is different, 'source' this script again "
+printf "before running 'letsencrypt'."
 echo
 echo
 echo "You can now run 'letsencrypt --help'."
diff --git a/letsencrypt-auto b/letsencrypt-auto
index aba8baec1..d163998aa 100755
--- a/letsencrypt-auto
+++ b/letsencrypt-auto
@@ -73,7 +73,7 @@ then
   fi
 fi
 
-echo -n "Updating letsencrypt and virtual environment dependencies..."
+printf "Updating letsencrypt and virtual environment dependencies..."
 if [ "$VERBOSE" = 1 ]  ; then
   echo
   $VENV_BIN/pip install -U setuptools
@@ -86,15 +86,15 @@ if [ "$VERBOSE" = 1 ]  ; then
   fi
 else
   $VENV_BIN/pip install -U setuptools > /dev/null
-  echo -n .
+  printf .
   $VENV_BIN/pip install -U pip > /dev/null
-  echo -n .
+  printf .
   # nginx is buggy / disabled for now...
   $VENV_BIN/pip install -U letsencrypt > /dev/null
-  echo -n .
+  printf .
   $VENV_BIN/pip install -U letsencrypt-apache > /dev/null
   if $VENV_BIN/pip freeze | grep -q letsencrypt-nginx ; then
-    echo -n .
+    printf .
     $VENV_BIN/pip install -U letsencrypt-nginx > /dev/null
   fi
   echo
diff --git a/letsencrypt/plugins/manual.py b/letsencrypt/plugins/manual.py
index 866965200..c76463f85 100644
--- a/letsencrypt/plugins/manual.py
+++ b/letsencrypt/plugins/manual.py
@@ -70,7 +70,7 @@ Are you OK with your IP being logged?
     CMD_TEMPLATE = """\
 mkdir -p {root}/public_html/{response.URI_ROOT_PATH}
 cd {root}/public_html
-echo -n {validation} > {response.URI_ROOT_PATH}/{encoded_token}
+printf "%s" {validation} > {response.URI_ROOT_PATH}/{encoded_token}
 # run only once per server:
 $(command -v python2 || command -v python2.7 || command -v python2.6) -c \\
 "import BaseHTTPServer, SimpleHTTPServer; \\
@@ -142,15 +142,14 @@ s.serve_forever()" """
             ct=response.CONTENT_TYPE, port=port)
         if self.conf("test-mode"):
             logger.debug("Test mode. Executing the manual command: %s", command)
-            # sh shipped with OS X does't support echo -n
-            executable = "/bin/bash" if sys.platform == "darwin" else None
+            # sh shipped with OS X does't support echo -n, but supports printf
             try:
                 self._httpd = subprocess.Popen(
                     command,
                     # don't care about setting stdout and stderr,
                     # we're in test mode anyway
                     shell=True,
-                    executable=executable,
+                    executable=None,
                     # "preexec_fn" is UNIX specific, but so is "command"
                     preexec_fn=os.setsid)
             except OSError as error:  # ValueError should not happen!