I've got the mod_rewrite set up and working but it's screwing up my page links

example here is my .htaccess

Options +FollowSymLinks
RewriteEngine on
RewriteBase /
RewriteRule ^profile/(.*)/$ /profile.php?un=$1


for the most part it works

if i type www.mywebsite.com/profile/fred/ www.mywebsite.com/profile.php?un=fred is what is
actually sent which is ok

however the problem is all my links on that page change..

my internal page links are change to www.mywebsite.com/users/fred/home.php when it should be
www.mywebsite.com/users/home.php why is 'fred' inserted in all the other page links?

Does anyone know why or how to fix this. Thanks