diff --git a/habitat/EZ.h b/habitat/EZ.h
index d689b6a..2fc1a21 100644
--- a/habitat/EZ.h
+++ b/habitat/EZ.h
@@ -140,7 +140,7 @@ class cURLslist
 
 public:
     cURLslist() { slist = NULL; };
-    void append(const char *s) { curl_slist_append(slist, s); };
+    void append(const char *s) { slist = curl_slist_append(slist, s); };
     ~cURLslist() { curl_slist_free_all(slist); };
     const struct curl_slist *get() { return slist; };
 };
diff --git a/src/EZ.cxx b/src/EZ.cxx
index 269234c..d1ea5c2 100644
--- a/src/EZ.cxx
+++ b/src/EZ.cxx
@@ -277,8 +277,14 @@ string cURL::post(const string &url, const string &data)
     MutexLock lock(mutex);
 
     reset();
+
+    /* Disable "Expect: 100-continue" - see issue #30 */
+    cURLslist headers;
+    headers.append("Expect:");
+
     setopt(CURLOPT_POSTFIELDS, data.c_str());
     setopt(CURLOPT_POSTFIELDSIZE, data.length());
+    setopt(CURLOPT_HTTPHEADER, headers.get());
 
     return cURL::perform(url);
 }
@@ -315,7 +321,13 @@ string cURL::put(const string &url, const string &data)
     MutexLock lock(mutex);
 
     reset();
+
+    /* issue #30 */
+    cURLslist headers;
+    headers.append("Expect:");
+
     setopt(CURLOPT_UPLOAD, 1);
+    setopt(CURLOPT_HTTPHEADER, headers.get());
 
     struct read_func_userdata userdata;
     userdata.data = &data;
diff --git a/tests/test_uploader.py b/tests/test_uploader.py
index 1a23d0b..f5dc4e1 100644
--- a/tests/test_uploader.py
+++ b/tests/test_uploader.py
@@ -282,6 +282,8 @@ class MockHTTPHandler(BaseHTTPServer.BaseHTTPRequestHandler):
 
         if support_100 and expect_100:
             self.wfile.write(self.protocol_version + " 100 Continue\r\n\r\n")
+            # See issue #30
+            raise AssertionError("Client used 100-continue!")
 
         length = self.headers.getheader('content-length')
         if length: