Here is my .htaccess file. This is for /%year%/%monthnum%/%day%/%postname%/ :
<IfModule mod_rewrite.c><br />
RewriteEngine On<br />
RewriteBase /<br />
RewriteCond %{REQUEST_FILENAME} -f [OR]<br />
RewriteCond %{REQUEST_FILENAME} -d<br />
RewriteRule ^.*$ - [S=38]<br />
RewriteRule ^feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?&feed=$1 [QSA,L]<br />
RewriteRule ^(feed|rdf|rss|rss2|atom)/?$ /index.php?&feed=$1 [QSA,L]<br />
RewriteRule ^page/?([0-9]{1,})/?$ /index.php?&paged=$1 [QSA,L]<br />
RewriteRule ^comments/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?&feed=$1&withcomments=1 [QSA,L]<br />
RewriteRule ^comments/(feed|rdf|rss|rss2|atom)/?$ /index.php?&feed=$1&withcomments=1 [QSA,L]<br />
RewriteRule ^comments/page/?([0-9]{1,})/?$ /index.php?&paged=$1 [QSA,L]<br />
RewriteRule ^author/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?author_name=$1&feed=$2 [QSA,L]<br />
RewriteRule ^author/([^/]+)/(feed|rdf|rss|rss2|atom)/?$ /index.php?author_name=$1&feed=$2 [QSA,L]<br />
RewriteRule ^author/([^/]+)/page/?([0-9]{1,})/?$ /index.php?author_name=$1&paged=$2 [QSA,L]<br />
RewriteRule ^author/([^/]+)/?$ /index.php?author_name=$1 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&day=$3&feed=$4 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&day=$3&feed=$4 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/page/?([0-9]{1,})/?$ /index.php?year=$1&monthnum=$2&day=$3&paged=$4 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/?$ /index.php?year=$1&monthnum=$2&day=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&feed=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&feed=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/page/?([0-9]{1,})/?$ /index.php?year=$1&monthnum=$2&paged=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/?$ /index.php?year=$1&monthnum=$2 [QSA,L]<br />
RewriteRule ^([0-9]{4})/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&feed=$2 [QSA,L]<br />
RewriteRule ^([0-9]{4})/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&feed=$2 [QSA,L]<br />
RewriteRule ^([0-9]{4})/page/?([0-9]{1,})/?$ /index.php?year=$1&paged=$2 [QSA,L]<br />
RewriteRule ^([0-9]{4})/?$ /index.php?year=$1 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/([^/]+)/trackback/?$ /index.php?year=$1&monthnum=$2&day=$3&name=$4&tb=1 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&day=$3&name=$4&feed=$5 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/([^/]+)/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&day=$3&name=$4&feed=$5 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/([^/]+)/page/?([0-9]{1,})/?$ /index.php?year=$1&monthnum=$2&day=$3&name=$4&paged=$5 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([0-9]{1,2})/([^/]+)(/[0-9]+)?/?$ /index.php?year=$1&monthnum=$2&day=$3&name=$4&page=$5 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&feed=$4&name=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([^/]+)/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&monthnum=$2&feed=$4&name=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([^/]+)/page/?([0-9]{1,})/?$ /index.php?year=$1&monthnum=$2&name=$3&paged=$4 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([^/]+)(/[0-9]+)?/?$ /index.php?year=$1&monthnum=$2&name=$3&page=$4 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([0-9]{1,2})/([^/]+)/trackback/?$ /index.php?year=$1&monthnum=$2&tb=1&name=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([^/]+)/feed/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&feed=$3&name=$2 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([^/]+)/(feed|rdf|rss|rss2|atom)/?$ /index.php?year=$1&feed=$3&name=$2 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([^/]+)/page/?([0-9]{1,})/?$ /index.php?year=$1&name=$2&paged=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([^/]+)(/[0-9]+)?/?$ /index.php?year=$1&name=$2&page=$3 [QSA,L]<br />
RewriteRule ^([0-9]{4})/([^/]+)/trackback/?$ /index.php?year=$1&tb=1&name=$2 [QSA,L]<br />
RewriteRule ^(.*)$ /wp-htaccess.php [L]<br />
</IfModule>