diff --git a/requests/_oauth.py b/requests/_oauth.py
index 8f44bf56..7105a602 100644
--- a/requests/_oauth.py
+++ b/requests/_oauth.py
@@ -16,8 +16,9 @@ try:
     from oauthlib.common import extract_params
     from oauthlib.oauth1.rfc5849 import (Client, SIGNATURE_HMAC, SIGNATURE_TYPE_AUTH_HEADER)
 except ImportError:
-    path = os.path.abspath('/'.join(__file__.split('/')[:-1]+['packages']))
+    directory = os.path.dirname(__file__)
+    path = os.path.join(directory, 'packages')
     sys.path.insert(0, path)
     from oauthlib.oauth1 import rfc5849
     from oauthlib.common import extract_params
-    from oauthlib.oauth1.rfc5849 import (Client, SIGNATURE_HMAC, SIGNATURE_TYPE_AUTH_HEADER)
\ No newline at end of file
+    from oauthlib.oauth1.rfc5849 import (Client, SIGNATURE_HMAC, SIGNATURE_TYPE_AUTH_HEADER)