fix for issue of saving document with buffer AND array on it

index.js

@@ -529,7 +529,7 @@ RedisClient.prototype.send_command = function () {
 
         for (i = 0, il = args.length, arg; i < il; i += 1) {
             arg = args[i];
-            if (arg.length === undefined) {
+            if (!(arg instanceof Buffer || arg instanceof String)) {
                 arg = String(arg);
             }
 

test.js

@@ -285,6 +285,17 @@ tests.HSET = function () {
     client.HSET(key, field2, value2, last(name, require_number(0, name)));
 };
 
+tests.HMSET_BUFFER_AND_ARRAY = function () {
+    // Saving a buffer and an array to the same document should not error
+    var key = "test hash",
+        field1 = "buffer",
+        value1 = new Buffer("abcdefghij"),
+        field2 = "array",
+        value2 = [],
+        name = "HSET";
+
+    client.HMSET(key, field1, value1, field2, value2, last(name, require_string("OK", name)));
+};
 
 tests.HMGET = function () {
     var key1 = "test hash 1", key2 = "test hash 2", name = "HMGET";