CodingForums.com - jQuery Problem with jquery masonry and fluid layout

I am having a problem with jquery masonry on a fluid layout.

It seems to not properly calculate the width of columns initially, see: http://www.complexd.co.uk/blog-intro/

There is a white border around images, where it should be flush. When I resize the window this disappears & is fine!

I can't work out why this is happening, any help would greatly be appreciated!

As a workaround I have tried setting a fixed width to the container div:

Code:

var mwidth = $('#blog-intro-container').width();

$('#blog-intro-container').css('width', mwidth);

However it still over calculates the width: http://www.complexd.co.uk/blog-intro-2/. I could hide with overflow hidden, but am still getting 1px gaps between columns & would like to work out why gaps appear in the first place...