.htaccess和HTTP_COOKIE值

In my .htaccess files:
For proper Cookies I use this, that's OK if I check whether there exists a cookie.

   RewriteCond %{HTTP_COOKIE} (my\_cookie) [NC]

But when I tried to check for zero values and use these choices, it fails to match cases:

RewriteCond %{HTTP_COOKIE} ^.*my\_cookie=0.*$ [NC]
RewriteCond %{HTTP_COOKIE} my\_cookie=0 [NC]
RewriteCond %{HTTP_COOKIE} (my\_cookie=0) [NC]

When I make print_r ( $_COOKIE ); I get this:

Array
(
    [analytics] => true
    [CakeCookie] => Array
        (
            [my_cookie] => 0
            [newuser] => 1
        )
)

How can I check the cookie value for this case?

After too many tryouts, this solved my issue:

RewriteCond %{HTTP_COOKIE} CakeCookie.*my\_cookie.*=0

I still don't know what would be exact pattern instead of .*
but this one works.

Im using same solution for handle language:

RewriteEngine On
RewriteBase /
RewriteCond %{HTTP_COOKIE} lang=([^;]+) [NC]
RewriteRule ^(.*)$ /$1?lang=%1 [NC,L,QSA]

but I checking value in php file. I hope that it will be helpful for u ;)