A fix for this is actually quite simple. Just use this code. (I changed the t=$thread[threadid] to p=$post[postid], so vB finds the thread and the correct page by the postnumber)
Code:
<!-- Link for post anchor -->
<a href="showthread.php?$session[sessionurl]p=$post[postid]#post$post[postid]" title="Anchor location for this post" style="text-decoration: none">§</a>
<!-- /Link for post anchor -->