diff --git a/ssl/kssl.c b/ssl/kssl.c
index a3a0596bf..dc54035d2 100644
--- a/ssl/kssl.c
+++ b/ssl/kssl.c
@@ -129,17 +129,20 @@
 #define krb5_timeofday           kssl_krb5_timeofday
 #define krb5_rc_default           kssl_krb5_rc_default
 
-#ifndef krb5_rc_initialize
+#ifdef krb5_rc_initialize
+#undef krb5_rc_initialize
+#endif
 #define krb5_rc_initialize   kssl_krb5_rc_initialize
-#endif
 
-#ifndef krb5_rc_get_lifespan
+#ifdef krb5_rc_get_lifespan
+#undef krb5_rc_get_lifespan
+#endif
 #define krb5_rc_get_lifespan kssl_krb5_rc_get_lifespan
-#endif
 
-#ifndef krb5_rc_destroy
-#define krb5_rc_destroy      kssl_krb5_rc_destroy
+#ifdef krb5_rc_destroy
+#undef krb5_rc_destroy
 #endif
+#define krb5_rc_destroy      kssl_krb5_rc_destroy
 
 #define valid_cksumtype      kssl_valid_cksumtype
 #define krb5_checksum_size   kssl_krb5_checksum_size