diff --git a/dlls/mshtml/mshtml_private.h b/dlls/mshtml/mshtml_private.h
index 5067b668497..d1d0d05010e 100644
--- a/dlls/mshtml/mshtml_private.h
+++ b/dlls/mshtml/mshtml_private.h
@@ -467,12 +467,14 @@ typedef struct {
     UINT url_scheme;
 } nsChannel;
 
-typedef struct ResponseHeader {
+typedef struct {
     struct list entry;
     WCHAR *header;
     WCHAR *data;
 } http_header_t;
 
+HRESULT set_http_header(struct list*,const WCHAR*,int,const WCHAR*,int);
+
 typedef struct {
     HRESULT (*qi)(HTMLDOMNode*,REFIID,void**);
     void (*destructor)(HTMLDOMNode*);
diff --git a/dlls/mshtml/navigate.c b/dlls/mshtml/navigate.c
index e4779893246..935a3b992f6 100644
--- a/dlls/mshtml/navigate.c
+++ b/dlls/mshtml/navigate.c
@@ -1104,6 +1104,7 @@ static HRESULT nsChannelBSC_on_response(BSCallback *bsc, DWORD response_code,
         LPCWSTR response_headers)
 {
     nsChannelBSC *This = NSCHANNELBSC_THIS(bsc);
+    HRESULT hres;
 
     This->nschannel->response_status = response_code;
 
@@ -1112,9 +1113,7 @@ static HRESULT nsChannelBSC_on_response(BSCallback *bsc, DWORD response_code,
 
         hdr_start = strchrW(response_headers, '\r');
         while(hdr_start) {
-            const WCHAR *colon;
-            struct ResponseHeader *new_header;
-            int len;
+            const WCHAR *colon, *value;
 
             hdr_start += 2;
             hdr_end = strchrW(hdr_start, '\r');
@@ -1132,35 +1131,14 @@ static HRESULT nsChannelBSC_on_response(BSCallback *bsc, DWORD response_code,
                 continue;
             }
 
-            new_header = heap_alloc(sizeof(struct ResponseHeader));
-            if(!new_header)
-                return E_OUTOFMEMORY;
+            value = colon+1;
+            while(*value == ' ')
+                value++;
 
-            len = colon - hdr_start;
-            new_header->header = heap_alloc((len + 1) * sizeof(WCHAR));
-            if(!new_header->header) {
-                heap_free(new_header);
-                return E_OUTOFMEMORY;
-            }
-            memcpy(new_header->header, hdr_start, len * sizeof(WCHAR));
-            new_header->header[len] = 0;
-
-            colon++;
-            while(*colon == ' ')
-                colon++;
-
-            len = hdr_end - colon;
-            new_header->data = heap_alloc((len + 1) * sizeof(WCHAR));
-            if(!new_header->data) {
-                heap_free(new_header->header);
-                heap_free(new_header);
-                return E_OUTOFMEMORY;
-            }
-            memcpy(new_header->data, colon, len * sizeof(WCHAR));
-            new_header->data[len] = 0;
-
-            list_add_head(&This->nschannel->response_headers, &new_header->entry);
-            TRACE("Adding header to list: (%s):(%s)\n", wine_dbgstr_w(new_header->header), wine_dbgstr_w(new_header->data));
+            hres = set_http_header(&This->nschannel->response_headers, hdr_start, colon-hdr_start,
+                    value, hdr_end-value);
+            if(FAILED(hres))
+                return hres;
 
             hdr_start = strchrW(hdr_start, '\r');
         }
diff --git a/dlls/mshtml/nsio.c b/dlls/mshtml/nsio.c
index fa0aa8d59df..9bef7f0a826 100644
--- a/dlls/mshtml/nsio.c
+++ b/dlls/mshtml/nsio.c
@@ -350,6 +350,43 @@ static nsresult get_channel_http_header(struct list *headers, const nsACString *
     return NS_OK;
 }
 
+HRESULT set_http_header(struct list *headers, const WCHAR *name, int name_len,
+        const WCHAR *value, int value_len)
+{
+    http_header_t *header;
+
+    TRACE("%s: %s\n", debugstr_wn(name, name_len), debugstr_wn(value, value_len));
+
+    header = find_http_header(headers, name, name_len);
+    if(header) {
+        WCHAR *new_data;
+
+        new_data = heap_strndupW(value, value_len);
+        if(!new_data)
+            return E_OUTOFMEMORY;
+
+        heap_free(header->data);
+        header->data = new_data;
+    }else {
+        header = heap_alloc(sizeof(http_header_t));
+        if(!header)
+            return E_OUTOFMEMORY;
+
+        header->header = heap_strndupW(name, name_len);
+        header->data = heap_strndupW(value, value_len);
+        if(!header->header || !header->data) {
+            heap_free(header->header);
+            heap_free(header->data);
+            heap_free(header);
+            return E_OUTOFMEMORY;
+        }
+
+        list_add_tail(headers, &header->entry);
+    }
+
+    return S_OK;
+}
+
 static void free_http_headers(struct list *list)
 {
     http_header_t *iter, *iter_next;