Thanks, can be a usefull plugin, but is not really what i meant..
Results of my posts page http://ditwordtmijnsite.nl/vvtxt/blog/ (background of the posts is still transparent)
Result of a single post http://ditwordtmijnsite.nl/vvtxt/uncategorized/123/
And what i need on the posts page is would be something like this http://www.vanvondeltxt.nl/blog
Looking forward to your solution!