Pagination adds unwanted #38;

Hi everybody,

I’m performing my own search query via a self-defined function containing a search form. The search results are opened within an iframe on the same page; therefore I created my own search.php (in a child theme) which does not contain the usual header etc.

I’ve got the problem that pagination in the search results does not work; it has something to do with the following hidden input field in the search form, which makes me search only within posts:

<input type="hidden" name="post_type" value="post" />

The first search results page opens the right way, the url is

(url)/?s=xy&post_type=post

But when I click on “2” in the pagination, nothing happens. Only the displayed url changes to

(url)/?s=xy&post_type=post#038;post_type=post&paged=2

which obviously can’t work. If I delete the part “#038;post_type=post”, everything works. So, does anybody have a guess where this redundant part in the url comes from and how I can get rid of it? I’m using Vantage with a child theme; the pagination is called via

<?php vantage_content_nav( 'nav-below' ); ?>

in the search.php.

Thank you very much,

Tadaki