Use FSF md5 functions.

@@ -31,7 +31,7 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 #include <stdlib.h>
 #include <string.h>
-#include <md5-rsa.h>
+#include <md5.h>
 #include <ctype.h>
 #ifdef HAVE_STRINGS_H
 # include <strings.h>
@@ -811,12 +811,12 @@ const char * sieve_errname (int e)
 
 static int makehash(unsigned char hash[HASHSIZE], char *s1, char *s2)
 {
-    MD5_CTX ctx;
+  struct md5_ctx ctx;
 
-    MD5Init(&ctx);
-    MD5Update(&ctx, (unsigned char*) s1, strlen(s1));
-    MD5Update(&ctx, (unsigned char*) s2, strlen(s2));
-    MD5Final(hash, &ctx);
+  md5_init_ctx (&ctx);
+  md5_process_bytes (s1, strlen(s1), &ctx);
+  md5_process_bytes (s2, strlen(s2), &ctx);
+  md5_finish_ctx (&ctx, hash);
 
   return SIEVE_OK;
 }