./configure; make; make install cannot open shared object file: No such file or directory

Make sure you have $prefix/lib in either your /etc/ or LD_LIBRARY_PATH, where $prefix is where you installed libtorrent. To update the ld cache, run "ldconfig".

Non-blocking hostname lookup in curl

RTorrent will block on hostname lookup during tracker requests and http downloads. You can avoid this by compiling libcurl with 'cares' support, though this will be fixed later by using seperate threads within rTorrent.