diff --git a/lib/config-riscos.h b/lib/config-riscos.h
index 4ed31ace99099474b7499931aed9d003b8ee72f2..f62c21dffcc161dcaae0f1388d45d5f1f3f206c9 100644
--- a/lib/config-riscos.h
+++ b/lib/config-riscos.h
@@ -36,7 +36,7 @@
 #undef NEED_REENTRANT
 
 /* Define if you have the Kerberos4 libraries (including -ldes) */
-#undef KRB4
+#undef HAVE_KRB4
 
 /* Define if you want to enable IPv6 support */
 #undef ENABLE_IPV6
diff --git a/lib/config-vms.h b/lib/config-vms.h
index 9ce256731918b1a6d503a6b575fdf793c9bca406..0c95dccb11f37c68d40b7a9dd8f408c12c92a43b 100755
--- a/lib/config-vms.h
+++ b/lib/config-vms.h
@@ -50,7 +50,7 @@
 #undef NEED_REENTRANT
 
 /* Define if you have the Kerberos4 libraries (including -ldes) */
-#undef KRB4
+#undef HAVE_KRB4
 
 /* Define this to 'int' if ssize_t is not an available typedefed type */
 #undef ssize_t
diff --git a/lib/ftp.c b/lib/ftp.c
index 48c70612e751b6f1652a31da4b9a2ca0956ecd47..3f51dd638a292623efaae4aebdbf436c79056730 100644
--- a/lib/ftp.c
+++ b/lib/ftp.c
@@ -77,7 +77,7 @@
 #include "http.h" /* for HTTP proxy tunnel stuff */
 #include "ftp.h"
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
 #include "security.h"
 #include "krb4.h"
 #endif
@@ -377,7 +377,7 @@ CURLcode Curl_GetFTPResponse(ssize_t *nreadp, /* return number of bytes read */
   if(!result)
     code = atoi(buf);
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
   /* handle the security-oriented responses 6xx ***/
   /* FIXME: some errorchecking perhaps... ***/
   switch(code) {
@@ -467,7 +467,7 @@ CURLcode Curl_ftp_connect(struct connectdata *conn)
     return CURLE_FTP_WEIRD_SERVER_REPLY;
   }
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
   /* if not anonymous login, try a secure login */
   if(data->set.krb4) {
 
@@ -559,7 +559,7 @@ CURLcode Curl_ftp_connect(struct connectdata *conn)
        (the user logged in without password) */
     infof(data, "We have successfully logged in\n");
     if (conn->ssl[FIRSTSOCKET].use) {
-#ifdef KRB4
+#ifdef HAVE_KRB4
 	/* we are logged in (with Kerberos)
 	 * now set the requested protection level
 	 */
@@ -739,7 +739,7 @@ CURLcode Curl_ftp_done(struct connectdata *conn)
     }
   }
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
   Curl_sec_fflush_fd(conn, conn->sock[SECONDARYSOCKET]);
 #endif
   /* shut down the socket to inform the server we're done */
diff --git a/lib/krb4.c b/lib/krb4.c
index bf8037d84ddc6240d87c9f7b4ae78c69cc8d17a4..5b09c1c6d454418f76ab8807a8045d4def1e9f34 100644
--- a/lib/krb4.c
+++ b/lib/krb4.c
@@ -41,7 +41,7 @@
 #include "setup.h"
 
 #ifndef CURL_DISABLE_FTP
-#ifdef KRB4
+#ifdef HAVE_KRB4
 
 #include "security.h"
 #include "base64.h"
@@ -402,5 +402,5 @@ CURLcode Curl_krb_kauth(struct connectdata *conn)
   return CURLE_OK;
 }
 
-#endif /* KRB4 */
+#endif /* HAVE_KRB4 */
 #endif /* CURL_DISABLE_FTP */
diff --git a/lib/security.c b/lib/security.c
index 1c83a18f9b4034b418e178e5877ebb5c2d541aaf..16746cdc950034658224953273fe55ce0792a83a 100644
--- a/lib/security.c
+++ b/lib/security.c
@@ -41,7 +41,7 @@
 #include "setup.h"
 
 #ifndef CURL_DISABLE_FTP
-#ifdef KRB4
+#ifdef HAVE_KRB4
 
 #define _MPRINTF_REPLACE /* we want curl-functions instead of native ones */
 #include <curl/mprintf.h>
@@ -90,7 +90,7 @@ static struct Curl_sec_client_mech *mechs[] = {
 #ifdef KRB5
   /* not supported */
 #endif
-#ifdef KRB4
+#ifdef HAVE_KRB4
     &Curl_krb4_client_mech,
 #endif
     NULL
@@ -478,5 +478,5 @@ Curl_sec_end(struct connectdata *conn)
   conn->mech=NULL;
 }
 
-#endif /* KRB4 */
+#endif /* HAVE_KRB4 */
 #endif /* CURL_DISABLE_FTP */
diff --git a/lib/sendf.c b/lib/sendf.c
index 1218377b7b49298647bf33a69589d3141fb490ab..701b6eadadaebfdcb5db1b20dd80e9ef53bac47d 100644
--- a/lib/sendf.c
+++ b/lib/sendf.c
@@ -48,7 +48,7 @@
 #define _MPRINTF_REPLACE /* use the internal *printf() functions */
 #include <curl/mprintf.h>
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
 #include "security.h"
 #endif
 #include <string.h>
@@ -278,12 +278,12 @@ CURLcode Curl_write(struct connectdata *conn,
 #else
   (void)conn;
 #endif
-#ifdef KRB4
+#ifdef HAVE_KRB4
     if(conn->sec_complete) {
       bytes_written = Curl_sec_write(conn, sockfd, mem, len);
     }
     else
-#endif /* KRB4 */
+#endif /* HAVE_KRB4 */
     {
       bytes_written = swrite(sockfd, mem, len);
     }
@@ -412,7 +412,7 @@ int Curl_read(struct connectdata *conn,
     (void)conn;
 #endif
     *n=0; /* reset amount to zero */
-#ifdef KRB4
+#ifdef HAVE_KRB4
     if(conn->sec_complete)
       nread = Curl_sec_read(conn, sockfd, buf, buffersize);
     else
diff --git a/lib/url.c b/lib/url.c
index b703d18f85dd59f6659ce31cbc09a525ce82e758..0dcc577afe0c981b36c62155cf30a5e0e2dd4866 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -127,7 +127,7 @@
 #define _MPRINTF_REPLACE /* use our functions only */
 #include <curl/mprintf.h>
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
 #include "security.h"
 #endif
 
diff --git a/lib/urldata.h b/lib/urldata.h
index 494cfb1398936dde8715fec397f26970f58ac58c..f178015417ca1c0849dc3bee88736a412ee4afc5 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -114,7 +114,7 @@
 #define MAX(x,y) ((x)>(y)?(x):(y))
 #endif
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
 /* Types needed for krb4-ftp connections */
 struct krb4buffer {
   void *data;
@@ -510,7 +510,7 @@ struct connectdata {
   char *newurl; /* This can only be set if a Location: was in the
 		   document headers */
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
   enum protection_level command_prot;
   enum protection_level data_prot;
   enum protection_level request_data_prot;
diff --git a/lib/version.c b/lib/version.c
index 3e8c88513f2e5a7945efcae8030fdbeac845f4f6..2e4d532ff67212d35ed883d249922861f397e6f2 100644
--- a/lib/version.c
+++ b/lib/version.c
@@ -102,7 +102,7 @@ char *curl_version(void)
   (void)num; /* no compiler warning please */
 #endif
 
-#ifdef KRB4
+#ifdef HAVE_KRB4
   sprintf(ptr, " krb4");
   ptr += strlen(ptr);
 #endif
@@ -167,7 +167,7 @@ static curl_version_info_data version_info = {
 #ifdef ENABLE_IPV6
   | CURL_VERSION_IPV6
 #endif
-#ifdef KRB4
+#ifdef HAVE_KRB4
   | CURL_VERSION_KERBEROS4
 #endif
 #ifdef USE_SSLEAY