Link on SVG image

Hi again!
I dinamically create in my Javascript a circle and set its attribute xlink:href to a document like "Detail.html?gr=11111", with the passage of a parameter. Why during visualization in a browser doesn't it see the parameter I've passed but it take me to the page "Detail.html"? It seems that it doesn't see all that is written after "?".
What could be the problem?
Thnaks! :)