I got this failure when trying to build ikiwiki version 3.20100403:

$ perl Makefile.PL INSTALL_BASE=/opt/ikiwiki PREFIX=
Writing Makefile for IkiWiki
$ make

...snip...

./pm_filter /opt/ikiwiki 3.20100403 /opt/ikiwiki/lib/perl5 < ikiwiki.in > ikiwiki.out
chmod +x ikiwiki.out
./pm_filter /opt/ikiwiki 3.20100403 /opt/ikiwiki/lib/perl5 < ikiwiki-transition.in > ikiwiki-transition.out
chmod +x ikiwiki-transition.out
./pm_filter /opt/ikiwiki 3.20100403 /opt/ikiwiki/lib/perl5 < ikiwiki-calendar.in > ikiwiki-calendar.out
chmod +x ikiwiki-calendar.out
HOME=/home/me /usr/bin/perl -Iblib/lib   ikiwiki.out -libdir . -dumpsetup ikiwiki.setup
Use of uninitialized value $IkiWiki::Setup::config{"setuptype"} in concatenation (.) or string at IkiWiki/Setup.pm line 53.
Can't locate IkiWiki/Setup/.pm in @INC (@INC contains: . /opt/ikiwiki/lib/perl5/i486-linux-gnu-thread-multi /opt/ikiwiki/lib/perl5 blib/lib /etc/perl /usr/local/lib/perl/5.10.1 /usr/local/share/perl/5.10.1 /usr/lib/perl5 /usr/share/perl5 /usr/lib/perl/5.10 /usr/share/perl/5.10 /usr/local/lib/site_perl .) at (eval 35) line 3.

make: *** [ikiwiki.setup] Error 2

Note that I had been trying to upgrade with an installed ikiwiki 3.20091114 already in place under /opt/ikiwiki. The build does not fail for me if I first remove the old ikiwiki installation, nor does it fail with 3.20100403 or newer installed at /opt/ikiwiki. Hence this is not really a critical bug, although it's somewhat perplexing to me why it ought to make a difference.

So, using INSTALL_BASE causes a 'use lib' to be hardcoded into the .out files; which overrides the -libdir and the -I, and so the old version of IkiWiki.pm is used. fixed --Joey