Error when publishing post after upgrading to 2.0.1

I upgraded from wp 2.0 to 2.0.1 and now everytime I try to publish a post, I get an internal Server Error but article is published correctly.

On my logs this is the error I get:

[Thu Feb 02 20:04:32 2006] [error] [client xx.xx.xx.xx.xx] malformed header from script. Bad header=!!!SELECT post_id, meta_: php-script, referer: https://www.xxxxxx.xxx/xxxxx/wp-admin/post.php?action=edit&post=273

If I just save it as draft it is ok . .is just when publishing.