diff --git a/patoolib/util.py b/patoolib/util.py
index ba6cc62..878fe12 100644
--- a/patoolib/util.py
+++ b/patoolib/util.py
@@ -86,16 +86,12 @@ def backtick (cmd):
     return subprocess.Popen(cmd, stdout=subprocess.PIPE).communicate()[0]
 
 
-def quote_arg (arg):
-    if " " in arg:
-        return '"%s"' % arg
-    return arg
-
-
 def run (cmd, **kwargs):
     """Run command without error checking.
     @return: command return code"""
-    log_info("running %s" % " ".join(map(quote_arg, cmd)))
+    args = (" ".join(map(shell_quote, cmd)),
+          ", ".join("%s=%s" % (k, shell_quote(v)) for k, v in kwargs.items()))
+    log_info("running %s with %s" % args)
     return subprocess.call(cmd, **kwargs)