Maybe is best way to show my problem in one example.
In my .htaccess :
RewriteRule ^catalog/[a-z0-9_-]+-([0-9]+)/[a-z0-9_-]+-([0-9]+)/[a-z0-9_-]+-([0-9]+)/ index.php?act=catalog&category=$1&color=$2&size=$3 [NC,L]
With the address
www.site.com/catalog/category-1/red-3/size-3/ this works excellent
But if you leave out the size, like
www.site.com/catalog/category-1/red-3/, I will be redirected to
I want to show all articles with category ID 1 and color which is ID 3.