diff --git a/crypto/engine/hw_sureware.c b/crypto/engine/hw_sureware.c
index c3bef29e8355aae17a1a98dedd88028343509a35..73a274cd485f7b5d4fdecf53bef376a1c41215b2 100644
--- a/crypto/engine/hw_sureware.c
+++ b/crypto/engine/hw_sureware.c
@@ -1024,7 +1024,7 @@ static int surewarehk_modexp(BIGNUM *r, const BIGNUM *a, const BIGNUM *p,
 						 (unsigned long *)p->d,
 						 a->top*sizeof(BN_ULONG),
 						 (unsigned long *)a->d,
-						 r->d);
+						 (unsigned long *)r->d);
 			surewarehk_error_handling(msg,SUREWARE_F_SUREWAREHK_MOD_EXP,ret);
 			if (ret==1)
 			{