diff --git a/server.go b/server.go
index e47d970..057a71d 100644
--- a/server.go
+++ b/server.go
@@ -50,9 +50,9 @@ type (
 
 	// Response can have messages and/or a result to return the to client.
 	Response struct {
-		ID       string                 `json:"id"`
-		Messages map[string][]string    `json:"messages,omitempty"`
-		Result   map[string]interface{} `json:"result,omitempty"`
+		ID       string              `json:"id"`
+		Messages map[string][]string `json:"messages,omitempty"`
+		Result   interface{}         `json:"result,omitempty"`
 	}
 
 	ident []byte
@@ -134,6 +134,7 @@ func (s *Server) Handle(w http.ResponseWriter, r *http.Request) {
 	}
 	c.Logf(LevelInfo, "method '%s' called with '%s'", req.Method, req.Params)
 	if err := handler(c, req, res); err != nil {
+		c.w.WriteHeader(http.StatusInternalServerError)
 		c.Logf(LevelError, "method '%s' returned an error: %s", req.Method, err)
 	}
 	if err := tx.Commit(); err != nil {