quilt marking

I hope someone has some advice for me.  I just finished hand quilting a project that took a very long time.  I used a Washout Cloth Marker to mark the quilting lines but it will not wash out!  Does anyone have any ideas on how to get those lines out of there? 

Here's a previous SMS forum post that might have some good suggestions: http://sewmamasew.com/forum/index.php?topic=708.0

Have you washed your quilt in a washing machine or have you just tried to dab it with some water and a cloth?  You might try soaking it in cold water and lightly rubbing the areas with a white cloth.  If that doesn't work and if the quilt is completed with binding, I would try to throw the whole thing in the washer.