--- a/ext/openssl/openssl.c
+++ b/ext/openssl/openssl.c
@@ -1482,7 +1482,9 @@
 	REGISTER_LONG_CONSTANT("PKCS7_NOSIGS", PKCS7_NOSIGS, CONST_CS|CONST_PERSISTENT);
 
 	REGISTER_LONG_CONSTANT("OPENSSL_PKCS1_PADDING", RSA_PKCS1_PADDING, CONST_CS|CONST_PERSISTENT);
+#ifdef RSA_SSLV23_PADDING
 	REGISTER_LONG_CONSTANT("OPENSSL_SSLV23_PADDING", RSA_SSLV23_PADDING, CONST_CS|CONST_PERSISTENT);
+#endif
 	REGISTER_LONG_CONSTANT("OPENSSL_NO_PADDING", RSA_NO_PADDING, CONST_CS|CONST_PERSISTENT);
 	REGISTER_LONG_CONSTANT("OPENSSL_PKCS1_OAEP_PADDING", RSA_PKCS1_OAEP_PADDING, CONST_CS|CONST_PERSISTENT);