Allow +'s in URL Rewrite

I want my url rewrite to allow Plus signs in the string so that i dont have the yucky %20 all over.

RewriteEngine on
RewriteRule 开发者_开发百科^/?([A-Za-z-\s_]+)/([A-Za-z-\s_]+)/([A-Za-z-\s_]+)$ display.php?a=$1&b=$2&c=$3 [L]  

How would i do this?

Escape it with \+ in your regex