WordPress MU

I have a problem..

I run a site using Wordpress MU, and i have 5 blogs that is running without any problems..

My problem is that i have now made 2 new blog and the users can't uplaod any pics..
I keep getting these error..

Unable to create directory /customers/7inch.dk/7inch.dk/httpd.www/blog/wp-content/blogs.dir/16/files/. Is its parent directory writable by the server?
Back to Image Uploading

What can be wrong??

Um, no disrespect entended but the error message is telling you what is wrong:

Is its parent directory writable by the server?

Please check to see if the wp-content (and then on down) subdirectory is writable by the server.