diff --git a/envoy/core.py b/envoy/core.py
index 61feb07..d349d78 100644
--- a/envoy/core.py
+++ b/envoy/core.py
@@ -137,7 +137,7 @@ def expand_args(command):
 
     # Prepare arguments.
     if isinstance(command, basestring):
-        splitter = shlex.shlex(command, posix=True)
+        splitter = shlex.shlex(command)
         splitter.whitespace = '|'
         splitter.whitespace_split = True
         command = []