I got a solution!
In file wpGoogleMaps.php in function wpgmaps_user_javascript_basic() need to change(line 630):
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script>
to:
<script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false&language=en"></script>