diff --git a/servlet/rest-servlet.go b/servlet/rest-servlet.go
index 7a38867..72c332d 100644
--- a/servlet/rest-servlet.go
+++ b/servlet/rest-servlet.go
@@ -96,7 +96,7 @@ func (s *RESTServlets) HandleGet(servletCtx server.ServletCtx, ctx *fasthttp.Req
 }
 
 func (s *RESTServlets) HandlePost(servletCtx server.ServletCtx, ctx *fasthttp.RequestCtx, mapping *MethodMapping) *csw.Error {
-	params := make([]string, 0)
+	params := make([][]byte, 0)
 	if nil != mapping.ParamKeys {
 		buf := ctx.PostBody()
 		if nil == buf || 0 == len(buf) {
@@ -113,11 +113,11 @@ func (s *RESTServlets) HandlePost(servletCtx server.ServletCtx, ctx *fasthttp.Re
 			if !ok {
 				return csw.NewError(fasthttp.StatusBadRequest, fmt.Errorf("Parameter for %s is not valied", k))
 			}
-			params = append(params, string(v))
+			params = append(params, v)
 		}
 	}
 
-	_, err := s.restRegistry.Invoke(mapping.Method, params, servletCtx, ctx)
+	_, err := s.restRegistry.InvokeWithBytes(mapping.Method, params, servletCtx, ctx)
 
 	if nil != err {
 		return csw.NewError(fasthttp.StatusInternalServerError, err)