Isn't this functionality a part of what [[plugins/toc]] needs and does? Then probably the [[plugins/toc]] plugin's code could be split into the part that implements the [[plugins/contrib/headinganchors]]'s functionality and the TOC generation itself. That will bring more order into the code and the set of available plugins. --Ivan Z.
+
+---
+
+A patch to make it more like MediaWiki:
+
+<pre>--- headinganchors.pm
++++ headinganchors.pm
+@@ -5,6 +5,7 @@
+ use warnings;
+ use strict;
+ use IkiWiki 2.00;
++use URI::Escape;
+
+ sub import {
+ hook(type => "sanitize", id => "headinganchors", call => \&headinganchors);
+@@ -14,9 +15,11 @@
+ my $str = shift;
+ $str =~ s/^\s+//;
+ $str =~ s/\s+$//;
+- $str = lc($str);
+- $str =~ s/[&\?"\'\.,\(\)!]//mig;
+- $str =~ s/[^a-z]/_/mig;
++ $str =~ s/\s/_/g;
++ $str =~ s/"//g;
++ $str =~ s/^[^a-zA-Z]/z-/; # must start with an alphabetical character
++ $str = uri_escape_utf8($str);
++ $str =~ s/%/./g;
+ return $str;
+ }
+ </pre>
+
+--Changaco