cons cvs fails to build package

[Timothee Besset]

Fresh download from subversions.gnu.org cvs server. cons -h gives build help 
and states:

Just type 'src/cons' to build using the target itself,
or type 'cons' to build using a cons in your path.

And what happens:

address@hidden:~/Id/cons$ ./src/cons.pl 
sed -e 's+__VERSION__+2.3+g' -e 's+__REVISION__+.1+g' 
build/export/cons-2.3.1/cons.pl > build/export/cons-2.3.1/cons
chmod 555 build/export/cons-2.3.1/cons
pod2man --section=1 --center="'Cons - Software Construction System'" 
--release=2.3.1 --official build/export/cons-2.3.1/cons > 
build/export/cons-2.3.1/cons.1
No directory specified for -I.
cons.pl: *** [build/export/cons-2.3.1/cons.1] Error 255
cons.pl: errors constructing build/export/cons-2.3.1/cons.1

That 'errors constructing build/export/cons-2.3.1/cons.1' leaves me
clueless. pod2man worked fine, the file is there. And I have no idea where
'No directory specified for -I.' comes from either.

ideas?

TTimo