diff --git a/novaclient/openstack/common/gettextutils.py b/novaclient/openstack/common/gettextutils.py
new file mode 100644
index 000000000..8a660b057
--- /dev/null
+++ b/novaclient/openstack/common/gettextutils.py
@@ -0,0 +1,50 @@
+# vim: tabstop=4 shiftwidth=4 softtabstop=4
+
+# Copyright 2012 Red Hat, Inc.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+gettext for openstack-common modules.
+
+Usual usage in an openstack.common module:
+
+    from novaclient.openstack.common.gettextutils import _
+"""
+
+import gettext
+import os
+
+_localedir = os.environ.get('novaclient'.upper() + '_LOCALEDIR')
+_t = gettext.translation('novaclient', localedir=_localedir, fallback=True)
+
+
+def _(msg):
+    return _t.ugettext(msg)
+
+
+def install(domain):
+    """Install a _() function using the given translation domain.
+
+    Given a translation domain, install a _() function using gettext's
+    install() function.
+
+    The main difference from gettext.install() is that we allow
+    overriding the default localedir (e.g. /usr/share/locale) using
+    a translation-domain-specific environment variable (e.g.
+    NOVA_LOCALEDIR).
+    """
+    gettext.install(domain,
+                    localedir=os.environ.get(domain.upper() + '_LOCALEDIR'),
+                    unicode=True)
diff --git a/novaclient/openstack/common/strutils.py b/novaclient/openstack/common/strutils.py
index fe8418e09..a9805373c 100644
--- a/novaclient/openstack/common/strutils.py
+++ b/novaclient/openstack/common/strutils.py
@@ -21,6 +21,12 @@ System-level utilities and helper functions.
 
 import sys
 
+from novaclient.openstack.common.gettextutils import _
+
+
+TRUE_STRINGS = ('1', 't', 'true', 'on', 'y', 'yes')
+FALSE_STRINGS = ('0', 'f', 'false', 'off', 'n', 'no')
+
 
 def int_from_bool_as_string(subject):
     """
@@ -37,24 +43,38 @@ def int_from_bool_as_string(subject):
     return bool_from_string(subject) and 1 or 0
 
 
-def bool_from_string(subject):
+def bool_from_string(subject, strict=False):
     """
     Interpret a string as a boolean.
 
-    Any string value in:
+    A case-insensitive match is performed such that strings matching 't',
+    'true', 'on', 'y', 'yes', or '1' are considered True and, when
+    `strict=False`, anything else is considered False.
 
-        ('True', 'true', 'On', 'on', 'Yes', 'yes', '1')
+    Useful for JSON-decoded stuff and config file parsing.
 
-    is interpreted as a boolean True.
-
-    Useful for JSON-decoded stuff and config file parsing
+    If `strict=True`, unrecognized values, including None, will raise a
+    ValueError which is useful when parsing values passed in from an API call.
+    Strings yielding False are 'f', 'false', 'off', 'n', 'no', or '0'.
     """
-    if isinstance(subject, bool):
-        return subject
-    if isinstance(subject, basestring):
-        if subject.strip().lower() in ('true', 'on', 'yes', '1'):
-            return True
-    return False
+    if not isinstance(subject, basestring):
+        subject = str(subject)
+
+    lowered = subject.strip().lower()
+
+    if lowered in TRUE_STRINGS:
+        return True
+    elif lowered in FALSE_STRINGS:
+        return False
+    elif strict:
+        acceptable = ', '.join(
+            "'%s'" % s for s in sorted(TRUE_STRINGS + FALSE_STRINGS))
+        msg = _("Unrecognized value '%(val)s', acceptable values are:"
+                " %(acceptable)s") % {'val': subject,
+                                      'acceptable': acceptable}
+        raise ValueError(msg)
+    else:
+        return False
 
 
 def safe_decode(text, incoming=None, errors='strict'):