lucy24 - 11:04 pm on Apr 4, 2013 (gmt 0)
Is this happening in htaccess or in your own server's config file?
If it's htaccess: The moment you add a rule using mod_rewrite, you will need to convert any existing rules using mod_alias (Redirect or RedirectMatch). This is because external redirects must happen before internal rewrites. On shared hosting you have no control over what order the mods load in. So you may be fine mixing mod_alias with mod_rewrite-- or you may have a big disaster. Don't take chances.
If it's your own server: You can continue using mod_alias if it loads after mod_rewrite, meaning it will excecute before. Execution order = opposite of load order.