authentication returnurl issue

I currently have a search page that uses a datagrid to display images and desc per product. I then have a repeater that lists the page numbers and each number is a linkbutton.

I am also doing url rewriting. So the url /folder/samsung-galaxy_bc-search_8.aspx would actually be search.aspx?id=8. I am using Intelligencia.UrlRewriter to do the rewriting.

This search is in a area where you have to sign in. So if a user copies /folder/samsung-galaxy_bc-search_8.aspx and then closes out completely then pastes this in the browser the returnurl is not /folder/samsung-galaxy_bc-search_8.aspx but it would appear as:
/login.aspx?ReturnUrl=%2ffolder%2fsearch.aspx%3fid%3d8&id=8

Is there a way to have the rewritten url in the returnurl?

I also have an issue with if they are on page 10 it doesn't keep that.

Any ideas if this is something worth trying to fix?