Not every query_post(...) works as weel for pagination,  sometimes it works for pagination when no need to use query_post(...) and just put this code as weel to show the list of the post :
<!--? php if (have_posts()): ?-->
And the other case is sometimes client site has no work for pagination when using our codes below :

query_posts( array(
'offset' => get_option('colabs_countpost'),
'cat' => $_cat
));

So we just need to implement this modification codes for query_post(...) to make pagination works as well :

query_posts( array(
'cat' => $_cat,
'posts_per_page' => get_option('colabs_countpost'),
'paged' => $paged
));