diff --git a/uv-win.c b/uv-win.c
index 0586aff0..c8fddfe5 100644
--- a/uv-win.c
+++ b/uv-win.c
@@ -296,6 +296,7 @@ static uv_err_code uv_translate_sys_error(int sys_errno) {
     case ERROR_CONNECTION_REFUSED:          return UV_ECONNREFUSED;
     case WSAECONNREFUSED:                   return UV_ECONNREFUSED;
     case WSAEFAULT:                         return UV_EFAULT;
+    case ERROR_INVALID_DATA:                return UV_EINVAL;
     case WSAEINVAL:                         return UV_EINVAL;
     case ERROR_TOO_MANY_OPEN_FILES:         return UV_EMFILE;
     case WSAEMFILE:                         return UV_EMFILE;
@@ -1212,6 +1213,8 @@ int uv_timer_init(uv_handle_t* handle, uv_close_cb close_cb, void* data) {
   handle->data = data;
   handle->flags = 0;
   handle->error = uv_ok_;
+  handle->timer_cb = NULL;
+  handle->repeat = 0;
 
   uv_refs_++;
 
@@ -1250,6 +1253,12 @@ int uv_timer_stop(uv_handle_t* handle) {
 
 
 int uv_timer_again(uv_handle_t* handle) {
+  /* If timer_cb is NULL that means that the timer was never started. */
+  if (!handle->timer_cb) {
+    uv_set_sys_error(ERROR_INVALID_DATA);
+    return -1;
+  }
+
   if (handle->flags & UV_HANDLE_ACTIVE) {
     RB_REMOVE(uv_timer_s, &uv_timers_, handle);
     handle->flags &= ~UV_HANDLE_ACTIVE;
@@ -1269,6 +1278,17 @@ int uv_timer_again(uv_handle_t* handle) {
 }
 
 
+int uv_timer_set_repeat(uv_handle_t* handle, int64_t repeat) {
+  handle->repeat = repeat;
+  return 0;
+}
+
+
+int64_t uv_timer_get_repeat(uv_handle_t* handle) {
+  return handle->repeat;
+}
+
+
 void uv_update_time() {
   LARGE_INTEGER counter;
 
diff --git a/uv.h b/uv.h
index 2070309c..d0104e2a 100644
--- a/uv.h
+++ b/uv.h
@@ -224,7 +224,17 @@ int uv_write(uv_req_t* req, uv_buf_t bufs[], int bufcnt);
 int uv_timer_init(uv_handle_t* handle, uv_close_cb close_cb, void* data);
 int uv_timer_start(uv_handle_t* handle, uv_loop_cb cb, int64_t timeout, int64_t repeat);
 int uv_timer_stop(uv_handle_t* handle);
+/* Stop the timer, and if it is repeating restart it using the repeat value 
+ * as the timeout. If the timer has never been started before it returns -1 and
+ * sets the error to UV_EINVAL. */
 int uv_timer_again(uv_handle_t* handle);
+/* Set the repeat value. Note that if the repeat value is set from a timer
+ * callback it does not immediately take effect. If the timer was nonrepeating
+ * before, it will have been stopped. If it was repeating, then the old repeat
+ * value will have been used to schedule the next timeout.
+ */
+int uv_timer_set_repeat(uv_handle_t* handle, int64_t repeat);
+int64_t uv_timer_get_repeat(uv_handle_t* handle);
 
 /* libev wrapper. Every active prepare handle gets its callback called
  * exactly once per loop iteration, just before the system blocks to wait