Problem with Redicet 301

Hi all!

I am running WordPress 3.2.1 in Multisite mode. I have transferred my site to WordPress from Joomla. Now I’m trying to create 301 redirects in the .htaccess file, but somehow it doesn’t work.

Say, I have the following url: ….site.ru/index.php/articles/video/video12345 (on Joomla). It does not exist anymore, as there’re WordPress files in the same directory now.
So I want to permanently redirect it to a page on one of my Multisite WordPress sites, …..site.ru/tv/article

Here’s the redirect I use:
Redirect 301 /index.php/articles/video/video12345 https://www...site.ru/tv/article

But in fact, what I get in the location bar is the new beginning of an URL and an old ending, like https://www...site.ru/tv/video12345

What’s more, if I make no redirects whatsoever in the .htacceess file, it redirects me the same way anyway, sometimes to categories that do not exist anymore (which I created while I was setting up my new wordpress installation)….

I was wondering if there can be some undeleted redirect data in some kind of a database like mySql, but found nothing…