Tokens in blocks configuration for List only pages
1) Enable the core PHP filter module

2) Use php in the visibility setting of your block. Notice that the path 'mypath' must be registered somehow before using this code. I mean that if the path 'mypath' does not exist at all any code here will not work.

&lt;?php
global $user;
$uid = $user-&gt;uid; // Get the logged in user id
// If the path is 'mypath/myarg' then arg(0) is 'mypath' and arg(1) is 'myarg'.
$show = (arg(0) == 'mypath') &amp;&amp; (arg(1) == $uid); // It must return both TRUE

return $show;
?&gt;


Alternative, use the Context module.