1 files changed, 1 insertions, 1 deletions
diff --git a/smtp.c b/smtp.c
index ef6cdb2d..584f9ece 100644
--- a/smtp.c
+++ b/smtp.c
@@ -97,7 +97,7 @@ static void SMTP_auth(int sock, char smtp_mode, char *username, char *password,
 		}
 		if (outlevel >= O_DEBUG)
 			report(stdout, GT_("Challenge decoded: %s\n"), b64buf);
-		hmac_md5(password, strlen(password),
+		hmac_md5((unsigned char *)password, strlen(password),
 			 b64buf, strlen(b64buf), digest, sizeof(digest));
 		snprintf(tmp, sizeof(tmp),
 		"%s %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",