diff --git a/libtelnet.h b/libtelnet.h
index e75cdff..4ea72c5 100644
--- a/libtelnet.h
+++ b/libtelnet.h
@@ -80,11 +80,13 @@
 #define TELNET_TELOPT_AUTHENTICATION 37
 #define TELNET_TELOPT_ENCRYPT 38
 #define TELNET_TELOPT_NEW_ENVIRON 39
-#define TELNET_TELOPT_COMPRESS 85
+#define TELNET_TELOPT_MSSP 70
 #define TELNET_TELOPT_COMPRESS2 86
 #define TELNET_TELOPT_ZMP 93
 #define TELNET_TELOPT_EXOPL 255
 
+#define TELNET_TELOPT_MCCP2 86
+
 /* libtelnet feature flags */
 #define TELNET_FLAG_PROXY (1<<0)