.htaccess rewrite rule for / - .htaccess

Question

I have a website where if I go to the URL http://mysite.com/community it shows page not found. But, the URL http://mysite.com/community/ correctly displays the page. How can I set up a rewrite for that "/" after community?
This is my present .htaccess:
Options +FollowSymLinks
Options +Indexes
RewriteEngine On
RewriteRule ^admin$ Admin/index.php?qstr=$1 [L]
RewriteRule ^(.*)/$ index.php?qstr=$1 [L]
These were the ones tried by me, but failed
First,
RewriteRule ^(.*)/community $1/community/ [L]
second,
RewriteRule /community /community/ [L]
All with different combinations of with and without [L].

Answer 1

From the Apache URL Rewrite Guide:
Trailing Slash Problem
Description:
Every webmaster can sing a song about the problem of the trailing slash on URLs referencing directories. If they are missing, the server dumps an error, because if you say /~quux/foo instead of /~quux/foo/ then the server searches for a file named foo. And because this file is a directory it complains. Actually it tries to fix it itself in most of the cases, but sometimes this mechanism need to be emulated by you. For instance after you have done a lot of complicated URL rewritings to CGI scripts etc.
Solution:
The solution to this subtle problem is to let the server add the trailing slash automatically. To do this correctly we have to use an external redirect, so the browser correctly requests subsequent images etc. If we only did a internal rewrite, this would only work for the directory page, but would go wrong when any images are included into this page with relative URLs, because the browser would request an in-lined object. For instance, a request for image.gif in /~quux/foo/index.html would become /~quux/image.gif without the external redirect!
So, to do this trick we write:
RewriteEngine on
RewriteBase /~quux/
RewriteRule ^foo$ foo/ [R]
The crazy and lazy can even do the following in the top-level .htaccess file of their homedir. But notice that this creates some processing overhead.
RewriteEngine on
RewriteBase /~quux/
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^(.+[^/])$ $1/ [R]

Answer 2

Well, after trying out all the above solutions as well as some of my own, I finally solved this. I'm definitely sure that this is NOT a complete solution but it sure solved it for the time being.
Solution: Just created an empty directory named "community" in the root folder. That's it!
But I'm still on the lookout for the actual solution to this.