This is too good to not report on, so for personal archiving reasons, I have put Alex’ Code below:

To your .htaccess file add:

RewriteRule ^search/(.+)?$ /index.php?s=$1 [QSA,L]

In your theme, look out for search.php or similar and change the form field to:

<form action=";/index.php" method="get" onsubmit="location.href='/search/' + encodeURIComponent(this.s.value).replace(/%20/g, '+'); return false;">

This is it, you are done!

/%year%/%monthnum%/
%postname%/

now say you want to get rid of the dates
(maybe seo-wise driven?)
you’d have

/%year%/%postname%/

But now all your posts (and post slugs) are outdated,
thus returning 404 or if you got the right
redirection rules return you to some error document.
That’s exactly what I did and troubled with.
Now there is this guy scotty from fucoder.com
who is a real genius.
He told me to solve this problem by
by adding an extra Mod_Rewrite rule before the rules
generated by WordPress.
In my case:

RewriteRule ^([0-9]{4})/
([0-9]{1,2})/([0-9]{1,2})/
([^/]+)/?$ /$4/ [L,R=301]

He told me to put that right after RewriteBase
to install this redirection and it worked wonders.
Thanks scotty!

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