Hi Abrantes,
This not an error, but you can solve it very easily, as you can see in Brazillian community Wiki:
http://www.softwarepublico.gov.br/dotlrn/clubs/openacs/xowiki/Reinstala%c3%a7%c3%a3o_do_AOLServer_-_Solu%c3%a7%c3%a3o_do_bug_no_Chat
Just run the following command before make install
make test=/usr/local/aolserver45
Then you can run:
make install NSHOME=/usr/local/aolserver45