jQuery SVG: id="path_for_x:5_y:5" couldn't be found

jQuery SVG: id="path_for_x:5_y:5" couldn't be found

Hi there, i'm using jQuery SVG for a while to create a game map with some tiles, i need to change opacity of some tiles (to draw a astar path finding result) but i'm stuck on a little issue:

  1. $("#path_for_x:5_y:5", mapSVG.root()).attr("opacity", "0.5");
the error is:

Uncaught Error: Syntax error, unrecognized expression: 5_y
  Does anyone know why? i tried to escape some characters like ":" or "_" but didn't fix the issue.