diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7d69fc1..bda2ad6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,10 @@
 * Fix: [#88](https://github.com/savonrb/httpi/issues/88) timeout and proxy options
   are now properly passed to the EM-HTTP-Request client.
 
+* Fix: [#90](https://github.com/savonrb/httpi/issues/90) we now raise an error if
+  you try to use Net::HTTP with HTTP digest authentication, because Net::HTTP does
+  not support digest authentication.
+
 ### 2.0.2 (2013-01-26)
 
 * Feature: Changed `HTTPI::Request#set_cookies` to accept an Array of `HTTPI::Cookie`
diff --git a/lib/httpi/adapter/net_http.rb b/lib/httpi/adapter/net_http.rb
index 050dbc5..851d37b 100644
--- a/lib/httpi/adapter/net_http.rb
+++ b/lib/httpi/adapter/net_http.rb
@@ -127,6 +127,10 @@ def request_client(type)
         request_client = request_class.new @request.url.request_uri, @request.headers
         request_client.basic_auth *@request.auth.credentials if @request.auth.basic?
 
+        if @request.auth.digest?
+          raise NotSupportedError, "Net::HTTP does not support HTTP digest authentication"
+        end
+
         request_client
       end
 
diff --git a/spec/httpi/adapter/net_http_spec.rb b/spec/httpi/adapter/net_http_spec.rb
index 1c2a3f6..bad776e 100644
--- a/spec/httpi/adapter/net_http_spec.rb
+++ b/spec/httpi/adapter/net_http_spec.rb
@@ -60,6 +60,14 @@
       response.body.should eq("basic-auth")
     end
 
+    it "does not support digest authentication" do
+      request = HTTPI::Request.new(@server.url + "digest-auth")
+      request.auth.digest("admin", "secret")
+
+      expect { HTTPI.get(request, adapter) }.
+        to raise_error(HTTPI::NotSupportedError, /does not support HTTP digest authentication/)
+    end
+
     it "supports ntlm authentication" do
       request = HTTPI::Request.new(@server.url + "ntlm-auth")
       request.auth.ntlm("tester", "vReqSoafRe5O")