Image_submit_tag, :get method and x&y issue

Rails
1

For search functionality I am using :get method to post the form. I am
also
using image_submit_tag.

<%= form_tag({:action => 'search'},{:method => :get}) %>
                <label>Search:</label>
                 <%= text_field_tag 'term' %>
                 <%= image_submit_tag "search.png",:name => nil%>
</form>

Problem is that when the form is submitted then firefox adds two more
params. This is what the URL looks like after submission.

http://localhost:3000/search?term=ROR&x=0&y=0

It should be noted that only firefox sends ‘x’ and ‘y’ params. IE
doesn’t
it. What should be done so that firefox doesn’t send ‘x’ and ‘y’
params?

Thanks