diff --git a/src/client/request.rs b/src/client/request.rs
index 442261cba7..9862aeae66 100644
--- a/src/client/request.rs
+++ b/src/client/request.rs
@@ -1,5 +1,6 @@
 //! Client Requests
 use std::old_io::{BufferedWriter, IoResult};
+use std::marker::PhantomData;
 
 use url::Url;
 
@@ -25,6 +26,8 @@ pub struct Request<W> {
     body: HttpWriter<BufferedWriter<Box<NetworkStream + Send>>>,
     headers: Headers,
     method: method::Method,
+
+    _marker: PhantomData<W>,
 }
 
 impl<W> Request<W> {
@@ -66,7 +69,8 @@ impl Request<Fresh> {
             headers: headers,
             url: url,
             version: version::HttpVersion::Http11,
-            body: stream
+            body: stream,
+            _marker: PhantomData,
         })
     }
 
@@ -136,7 +140,8 @@ impl Request<Fresh> {
             headers: self.headers,
             url: self.url,
             version: self.version,
-            body: stream
+            body: stream,
+            _marker: PhantomData,
         })
     }
 
diff --git a/src/client/response.rs b/src/client/response.rs
index 763f36cd2c..5ded928ef3 100644
--- a/src/client/response.rs
+++ b/src/client/response.rs
@@ -1,6 +1,7 @@
 //! Client Responses
 use std::num::FromPrimitive;
 use std::old_io::{BufferedReader, IoResult};
+use std::marker::PhantomData;
 
 use header;
 use header::{ContentLength, TransferEncoding};
@@ -23,6 +24,8 @@ pub struct Response<S = HttpStream> {
     pub version: version::HttpVersion,
     status_raw: RawStatus,
     body: HttpReader<BufferedReader<Box<NetworkStream + Send>>>,
+
+    _marker: PhantomData<S>,
 }
 
 impl Response {
@@ -72,6 +75,7 @@ impl Response {
             headers: headers,
             body: body,
             status_raw: raw_status,
+            _marker: PhantomData,
         })
     }
 
@@ -98,6 +102,7 @@ mod tests {
     use std::borrow::Cow::Borrowed;
     use std::boxed::BoxAny;
     use std::old_io::BufferedReader;
+    use std::marker::PhantomData;
 
     use header::Headers;
     use header::TransferEncoding;
@@ -119,7 +124,8 @@ mod tests {
             headers: Headers::new(),
             version: version::HttpVersion::Http11,
             body: EofReader(BufferedReader::new(box MockStream::new() as Box<NetworkStream + Send>)),
-            status_raw: RawStatus(200, Borrowed("OK"))
+            status_raw: RawStatus(200, Borrowed("OK")),
+            _marker: PhantomData,
         };
 
         let b = res.into_inner().downcast::<MockStream>().ok().unwrap();
diff --git a/src/header/common/authorization.rs b/src/header/common/authorization.rs
index 1c891c51c8..b36183d7bc 100644
--- a/src/header/common/authorization.rs
+++ b/src/header/common/authorization.rs
@@ -22,7 +22,7 @@ impl<S: Scheme> DerefMut for Authorization<S> {
     }
 }
 
-impl<S: Scheme + 'static> Header for Authorization<S> {
+impl<S: Scheme + 'static> Header for Authorization<S> where <S as FromStr>::Err: 'static {
     fn header_name() -> &'static str {
         "Authorization"
     }
@@ -43,7 +43,7 @@ impl<S: Scheme + 'static> Header for Authorization<S> {
     }
 }
 
-impl<S: Scheme + 'static> HeaderFormat for Authorization<S> {
+impl<S: Scheme + 'static> HeaderFormat for Authorization<S> where <S as FromStr>::Err: 'static {
     fn fmt_header(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
         match Scheme::scheme(None::<S>) {
             Some(scheme) => try!(write!(fmt, "{} ", scheme)),
diff --git a/src/server/response.rs b/src/server/response.rs
index 1e3604b0e7..e6fbb9cf99 100644
--- a/src/server/response.rs
+++ b/src/server/response.rs
@@ -3,6 +3,7 @@
 //! These are responses sent by a `hyper::Server` to clients, after
 //! receiving a request.
 use std::old_io::IoResult;
+use std::marker::PhantomData;
 
 use time::now_utc;
 
@@ -22,7 +23,9 @@ pub struct Response<'a, W = Fresh> {
     // The status code for the request.
     status: status::StatusCode,
     // The outgoing headers on this response.
-    headers: header::Headers
+    headers: header::Headers,
+
+    _marker: PhantomData<W>
 }
 
 impl<'a, W> Response<'a, W> {
@@ -42,7 +45,8 @@ impl<'a, W> Response<'a, W> {
             status: status,
             version: version,
             body: body,
-            headers: headers
+            headers: headers,
+            _marker: PhantomData,
         }
     }
 
@@ -60,7 +64,8 @@ impl<'a> Response<'a, Fresh> {
             status: status::StatusCode::Ok,
             version: version::HttpVersion::Http11,
             headers: header::Headers::new(),
-            body: ThroughWriter(stream)
+            body: ThroughWriter(stream),
+            _marker: PhantomData,
         }
     }
 
@@ -119,7 +124,8 @@ impl<'a> Response<'a, Fresh> {
             version: self.version,
             body: stream,
             status: self.status,
-            headers: self.headers
+            headers: self.headers,
+            _marker: PhantomData,
         })
     }