public RawAPIResponse callPostAPI(String relativeUrl, Map<String, String> parameters) throws FacebookException {
        ensureAuthorizationEnabled();

        String path = relativeUrl;
        if (relativeUrl.startsWith("/")) {
            path = relativeUrl.substring(1);
        }

        HttpResponse res;
        if (parameters != null && parameters.size() > 0) {
            final HttpParameter[] httpParameters = new HttpParameter[parameters.size()];
            int i = 0;
            for (final String p : parameters.keySet()) {
                httpParameters[i++] = new HttpParameter(p, parameters.get(p));
            }
            res = post(buildEndpoint(path), httpParameters);
        } else {
            res = post(buildEndpoint(path));
        }

        // not supports "JSONStore" option because this method returns the json object itself.
        return new RawAPIResponseImpl(res);
    }