Subdirectory based multi-site, can’t upload images

Hey WordPress.

I installed a fresh copy of WordPress 3.0 and decided to create a network of blogs to manage as I want to have different themes and template for different parts of my website. I figured I could create the network to manage them from a single account instead of creating multiple admin accounts.

I can’t upload images in any of my subdirectory sites. This is the error message I get, I’m sure you’ve all seen it.

“DSC_0479.jpg” has failed to upload due to an error
Unable to create directory /abc/defg/public_html/wp-content/blogs.dir/2/files/2010/06. Is its parent directory writable by the server

I checked my folder permissions and the upload folder listed on all sites in my network. All permissions are set to 755. I switched them to 777 for a bit with no success. The upload directory is the same for all sites but it from what I’ve read it doesn’t matter because the uploads from subdirectory sites in the network have to go through blogs.dir anyway before they’re redirected? I really don’t understand that bit at all. Fact is, I can upload without a problem from the first site I made but I can’t from any of the subdirectory network websites.

I apologize for being vague, but I really can’t detail further.. most things I’ve found on the topic keep telling me to check my permissions but that’s not the problem.. otherwise the first site I made wouldn’t be able to upload any images either, right?

appreciate the help.