diff --git a/lib/http.c b/lib/http.c
index e277194fbd1f43f47ebbe804971013b1ec87b14c..61b9f48933cca77a9bd580a55fc093d48d71a545 100644
--- a/lib/http.c
+++ b/lib/http.c
@@ -247,7 +247,7 @@ CURLcode http_auth_headers(struct connectdata *conn,
       if((data->state.authwant == CURLAUTH_GSSNEGOTIATE) &&
          data->state.negotiate.context && 
          !GSS_ERROR(data->state.negotiate.status)) {
-        auth="GSS-Negotiate";
+        auth=(char *)"GSS-Negotiate";
         result = Curl_output_negotiate(conn);
         if (result)
           return result;