uri problem

[eluser]dimis[/eluser]
I have a form that change the language of the site and then redirect at the previous page.
I use the

Code:

$this->uri->uri_string

.
My problem is that I have a search page with pagination and I use the enable query string (true), so when I am at the second page of the search page (/search?per_page=10)the

Code:

$this->uri->uri_string

returns nothing.How can I solve it?
Dimis