Ok. It seems that I had no libs in $libdir.
I ./configure(d), make, make install again with little changes and
everything is fine now. I have just installed plpgsql to one of my
databases.
Here is what worked:
./configure --prefix=/usr/local/pgsql --enable-threads=posix
--mandir=/usr/share/man --enable-nls=de,en --with-perl
--enable-thread-safety
Here is what I had before and what delivered only a plperl.so in
/usr/lib/postgresql:
./configure --enable-threads=posix --with-local-prefix=/usr/local
--mandir=/usr/share/man --libdir=/usr/lib --enable-nls=de,en
--with-perl --enable-thread-safety
But now everything is fine, thanks for help
Greetings,
Robert