diff --git a/owlps-listener/owlps-listenerd.c b/owlps-listener/owlps-listenerd.c
index b5bfccb..dfa85ad 100644
--- a/owlps-listener/owlps-listenerd.c
+++ b/owlps-listener/owlps-listenerd.c
@@ -1375,6 +1375,9 @@ void extract_radiotap_data(const u_char *pkt_data,
               rtap_fields[RTAP_FCS] = owl_true;
               rtap_position += RTAP_L_FCS ;
               break ;
+            default:
+              fprintf(stderr, "Warning! Radiotap field not handled: bit"
+                      " %d. This should be investigated.", i) ;
             }
         }
       rtap_presentflags /= 2 ;