compile error "undefined reference"

[ghost]

trying to compile with RS 0.5.4 on ubuntu 12.04.1

g++ -m64 -Wl,-O1 -o retroshare-ncurses temp/linux-g++-64/obj/retroshare-ncurses.o temp/linux-g++-64/obj/notifytxt.o temp/linux-g++-64/obj/Menu.o temp/linux-g++-64/obj/Cli.o temp/linux-g++-64/obj/FriendsWindow.o -L/usr/lib/x86_64-linux-gnu ../../libretroshare/src/lib/libretroshare.a -lssl -lgpgme -lupnp -lixml -lgnome-keyring -lcrypto -ldl -lmenu -lncurses ../../libbitdht/src/lib/libbitdht.a -lQtGui -lQtCore -lpthread
../../libretroshare/src/lib/libretroshare.a(pgphandler.o): In function PGPHandler::makeRadixEncodedPGPKey(ops_keydata const*, bool)': /vcs/soft/retroshare/libretroshare/src/pgp/pgphandler.cc:456: undefined reference toops_setup_memory_write'
/vcs/soft/retroshare/libretroshare/src/pgp/pgphandler.cc:466: undefined reference to ops_write_transferable_secret_key_from_packet_data' /vcs/soft/retroshare/libretroshare/src/pgp/pgphandler.cc:475: undefined reference toops_writer_close'
/home/sk/vcs/soft/retroshare/libretroshare/src/pgp/pgphandler.cc:477: undefined reference to ops_memory_get_length' /vcs/soft/retroshare/libretroshare/src/pgp/pgphandler.cc:477: undefined reference toops_memory_get_data'
/vcs/soft/retroshare/libretroshare/src/pgp/pgphandler.cc:478: undefined reference to ops_teardown_memory_write' /vcs/soft/retroshare/libretroshare/src/pgp/pgphandler.cc:461: undefined reference toops_write_transferable_public_key_from_packet_data'

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