diff --git a/mystic/mis_client_binkp.pas b/mystic/mis_client_binkp.pas
index fd1f492..c1d3cf5 100644
--- a/mystic/mis_client_binkp.pas
+++ b/mystic/mis_client_binkp.pas
@@ -426,7 +426,7 @@ Begin
 
                         MD5Challenge := Digest2String(Str);
 
-                        SendFrame (M_NUL, 'OPT MD5-' + MD5Challenge);
+                        SendFrame (M_NUL, 'OPT CRAM-MD5-' + MD5Challenge);
 
                         AuthState := SendWelcome;
                       End;