Google gives different PR to google.com and google.COM (which are technically same site), see the complete post at http://www.idealwebtools.com/blog/google-toolbar-icann/ with images.

[Philipp, as you have asked I am adding the post to the forums, let me know if I am violating any TOS, thanks]

http://www.idealwebtools.com/blog/wp-content/uploads/2007/05/google-pagerankerror.gif

Here is the image