diff --git a/cowrie/core/honeypot.py b/cowrie/core/honeypot.py
index 505531f..52f442e 100644
--- a/cowrie/core/honeypot.py
+++ b/cowrie/core/honeypot.py
@@ -136,8 +136,7 @@ class HoneyPotShell(object):
         """
         """
         log.msg('CMD: %s' % (line,))
-        self.lexer = shlex.shlex(punctuation_chars=True);
-        self.lexer.push_source(line)
+        self.lexer = shlex.shlex(instream=line, punctuation_chars=True);
         tokens = []
         while True:
             try:
diff --git a/cowrie/core/shlex.py b/cowrie/core/shlex.py
index 4e4ace5..a482d21 100644
--- a/cowrie/core/shlex.py
+++ b/cowrie/core/shlex.py
@@ -23,8 +23,7 @@ class shlex:
     def __init__(self, instream=None, infile=None, posix=False,
                  punctuation_chars=False):
         if isinstance(instream, str):
-            instream = StringIO(instream)
-            #instream = BytesIO(instream)
+            instream = BytesIO(instream)
         if instream is not None:
             self.instream = instream
             self.infile = infile
@@ -83,7 +82,6 @@ class shlex:
     def push_source(self, newstream, newfile=None):
         "Push an input source onto the lexer's input source stack."
         if isinstance(newstream, str):
-            #newstream = StringIO(newstream)
             newstream = BytesIO(newstream)
         self.filestack.appendleft((self.infile, self.instream, self.lineno))
         self.infile = newfile