Export the Extensions URL functions for overriding.
diff --git a/openstack/common/extensions/requests.go b/openstack/common/extensions/requests.go
index 8b3f0d2..ed5ea4b 100644
--- a/openstack/common/extensions/requests.go
+++ b/openstack/common/extensions/requests.go
@@ -9,7 +9,7 @@
 // Get retrieves information for a specific extension using its alias.
 func Get(c *gophercloud.ServiceClient, alias string) GetResult {
 	var res GetResult
-	_, err := perigee.Request("GET", extensionURL(c, alias), perigee.Options{
+	_, err := perigee.Request("GET", ExtensionURL(c, alias), perigee.Options{
 		MoreHeaders: c.Provider.AuthenticatedHeaders(),
 		Results:     &res.Resp,
 		OkCodes:     []int{200},
@@ -21,7 +21,7 @@
 // List returns a Pager which allows you to iterate over the full collection of extensions.
 // It does not accept query parameters.
 func List(c *gophercloud.ServiceClient) pagination.Pager {
-	return pagination.NewPager(c, listExtensionURL(c), func(r pagination.LastHTTPResponse) pagination.Page {
+	return pagination.NewPager(c, ListExtensionURL(c), func(r pagination.LastHTTPResponse) pagination.Page {
 		return ExtensionPage{pagination.SinglePageBase(r)}
 	})
 }