I have ikiwiki_3.20111229 installed on Debian Squeeze (Perl 5.10.1, UTF-8
locale). The attachment plugin mangles UTF8-encoded attachment filenames if
the name contains multibyte characters, e.g. "lää.png" becomes "lÃ¤Ã¤.png".
Apparently glob returns byte strings which are subject to implicit
upgrading when concatenated with Perl strings. The following patch fixes
the problem for me:

----

    diff -r -U 1 a/attachment.pm b/attachment.pm
    --- a/attachment.pm	2012-01-13 23:07:29.000000000 +0200
    +++ b/attachment.pm	2012-01-13 23:33:07.000000000 +0200
    @@ -274,2 +274,3 @@
     	foreach my $filename (glob("$dir/*")) {
    +	    $filename=Encode::decode_utf8($filename);
     		next unless -f $filename;
    @@ -347,2 +348,3 @@
     	foreach my $file (glob("$dir/*")) {
    +	    $file = Encode::decode_utf8($file);
     		next unless -f $file;

> Seems it only mangled display of the just-uploaded attachment's filename,
> the attachment was otherwise saved to disk with a valid UTF-8 name, and
> doing other stuff with it also was ok. In any case, I applied your patch,
> thanks. [[done]] --[[Joey]]
