can't see what the onclick(ajaxpage) is doing, but the only thing I can see is that you aren't setting the <a> (so nothing is being entered in to the $_GET array)
unless thats what the onclick is doing, can't really tell.
my code below will make the link "page.php#?division=division"
which should then work with your function.
also check the source to see if the hidden field is being set.
print "<td valign=\"top\" align=\"center\" width=\"30\"><a href=\"#?division=".$row['division']."\" onclick=\"ajaxpage('editdivision', 'content', '".$row['division']."'); return false;\">Edit</a></td>";