diff --git a/include/polarssl/bignum.h b/include/polarssl/bignum.h
index 9afc948d0..ad033084c 100644
--- a/include/polarssl/bignum.h
+++ b/include/polarssl/bignum.h
@@ -104,6 +104,7 @@ typedef unsigned long  t_udbl;
         (defined(__sparc__) && defined(__arch64__))  || \
         defined(__s390x__) )
     typedef unsigned int t_udbl __attribute__((mode(TI)));
+    #define POLARSSL_HAVE_LONGLONG
     #else
       #if defined(POLARSSL_HAVE_LONGLONG)
       typedef unsigned long long t_udbl;
diff --git a/include/polarssl/bn_mul.h b/include/polarssl/bn_mul.h
index f278dd04e..a6a2c65fb 100644
--- a/include/polarssl/bn_mul.h
+++ b/include/polarssl/bn_mul.h
@@ -41,7 +41,7 @@
 #ifndef POLARSSL_BN_MUL_H
 #define POLARSSL_BN_MUL_H
 
-#include "config.h"
+#include "bignum.h"
 
 #if defined(POLARSSL_HAVE_ASM)