query_post problem showing less on second page

Hello I have a query_post problem.

I try to create a portfolio page. I have created a page where I output one category from my “blogg”. On this page I try to output 6 posts on the first page. And then if I have for example 7 posts in this category I would like the output when you click the button “old entries” to just be one post.

I have used this code before the loop:
<?php query_posts(‘cat=3&showposts=6’); ?>

I understand that I need a if and else statement but I haven′t been able to find anything that fits my need.

Thanx in advanced!

//OLA