change javascripts default image directory?

Hi,
I am using overlibmws.js library to add some dynamic effect to my rails
web pages. But the server can not find the gif files that required by
javascripts. It always tries to search in , for example
,"/experiment/index/" this directory. I changed the "OLbubbleImageDir"
setting to "public/images", which is the directory I put those gif files,
but does not work. Server gives a 404 error.

I 'd like to know how to change the deault searching directory of
javascripts from ".../index" to "public/images" or other place in rails
project. I do not know anything about javascripts, except the syntax looks
similiar to java.

Thanks in advance.