diff --git a/oauth3.core.js b/oauth3.core.js
index f14d429..0dbb1c8 100644
--- a/oauth3.core.js
+++ b/oauth3.core.js
@@ -800,7 +800,7 @@
         opts = opts || {};
         providerUri = OAUTH3.url.normalize(providerUri);
 
-        if (providerUri.match(OAUTH3._browser.window.location.hostname)) {
+        if (OAUTH3.uri.normalize(providerUri).replace(/\/.*/, '') === OAUTH3.uri.normalize(OAUTH3._browser.window.location.hostname)) {
           console.warn("It looks like you're a provider checking for your own directive,"
             + " so we we're just gonna use"
             + " OAUTH3.request({ method: 'GET', url: '.well-known/oauth3/directive.json' })");