diff --git a/source/lib/netapi/netapi.c b/source/lib/netapi/netapi.c
index ce00054e6e9..5c3f7ec465a 100644
--- a/source/lib/netapi/netapi.c
+++ b/source/lib/netapi/netapi.c
@@ -205,15 +205,20 @@ const char *libnetapi_errstr(NET_API_STATUS status)
 ****************************************************************/
 
 NET_API_STATUS libnetapi_set_error_string(struct libnetapi_ctx *ctx,
-					  const char *error_string)
+					  const char *format, ...)
 {
+	va_list args;
+
 	TALLOC_FREE(ctx->error_string);
-	ctx->error_string = talloc_strdup(ctx, error_string);
+
+	va_start(args, format);
+	ctx->error_string = talloc_vasprintf(ctx, format, args);
+	va_end(args);
+
 	if (!ctx->error_string) {
 		return W_ERROR_V(WERR_NOMEM);
 	}
 	return NET_API_STATUS_SUCCESS;
-
 }
 
 /****************************************************************
diff --git a/source/lib/netapi/netapi.h b/source/lib/netapi/netapi.h
index 274a167d536..67bb8a8fcae 100644
--- a/source/lib/netapi/netapi.h
+++ b/source/lib/netapi/netapi.h
@@ -57,46 +57,73 @@ NET_API_STATUS libnetapi_set_username(struct libnetapi_ctx *ctx, const char *use
 NET_API_STATUS libnetapi_set_password(struct libnetapi_ctx *ctx, const char *password);
 NET_API_STATUS libnetapi_set_workgroup(struct libnetapi_ctx *ctx, const char *workgroup);
 const char *libnetapi_errstr(NET_API_STATUS status);
-NET_API_STATUS libnetapi_set_error_string(struct libnetapi_ctx *ctx, const char *error_string);
+NET_API_STATUS libnetapi_set_error_string(struct libnetapi_ctx *ctx, const char *format, ...);
 const char *libnetapi_get_error_string(struct libnetapi_ctx *ctx, NET_API_STATUS status);
 
 
 /****************************************************************
+ NetApiBufferFree
 ****************************************************************/
 
 NET_API_STATUS NetApiBufferFree(void *buffer);
 
 /****************************************************************
+ NetJoinDomain
 ****************************************************************/
 
-/* wkssvc */
 NET_API_STATUS NetJoinDomain(const char *server,
 			     const char *domain,
 			     const char *account_ou,
 			     const char *account,
 			     const char *password,
 			     uint32_t join_options);
+
+/****************************************************************
+ NetUnjoinDomain
+****************************************************************/
+
 NET_API_STATUS NetUnjoinDomain(const char *server_name,
 			       const char *account,
 			       const char *password,
 			       uint32_t unjoin_flags);
+
+/****************************************************************
+ NetGetJoinInformation
+****************************************************************/
+
 NET_API_STATUS NetGetJoinInformation(const char *server_name,
 				     const char **name_buffer,
 				     uint16_t *name_type);
 
-/* srvsvc */
+/****************************************************************
+ NetServerGetInfo
+****************************************************************/
+
 NET_API_STATUS NetServerGetInfo(const char *server_name,
 				uint32_t level,
 				uint8_t **buffer);
+
+/****************************************************************
+ NetServerSetInfo
+****************************************************************/
+
 NET_API_STATUS NetServerSetInfo(const char *server_name,
 				uint32_t level,
 				uint8_t *buffer,
 				uint32_t *parm_error);
 
-/* netlogon */
+/****************************************************************
+ NetGetDCName
+****************************************************************/
+
 NET_API_STATUS NetGetDCName(const char *server_name,
 			    const char *domain_name,
 			    uint8_t **buffer);
+
+/****************************************************************
+ NetGetAnyDCName
+****************************************************************/
+
 NET_API_STATUS NetGetAnyDCName(const char *server_name,
 			       const char *domain_name,
 			       uint8_t **buffer);