buildworld error in pam-ssh

Hello: I'm using 4 stable and i'want to upgrade to current. When I do make buildworld, I get the next error: ... ...  libpam/modules/pam-ssh make: don't know how to make /usr/obj/usr/src/i386/usr/lib/libssh.a Stop Error code 2 1 error Erro code 2 1 error   What can I do to fix it. Thanks

make builworld pam-ssh error

Hello: When I do make buildworld, I get the next error: ... ... libpam/modules/pam-ssh make: don't know how to make /usr/obj/usr/src/i386/usr/lib/libssh.a Stop Error code 2 1 error Erro code 2 1 error I'm using 4 stable and i'want to upgrade to current. What can I do to fix it. Thanks