While I was doing snort -c /usr/local/snort/etc/snort.conf --dump-dynamic-rules=/usr/local/snort/so_rules CentOS6.2 received an error like this:

error while loading shared libraries:
libsfbpf.so.0: cannot open shared object file: No such file or directory

The same error occurs when doing snort -c /usr/local/snort/etc/snort.conf -T

The way to solve this is to type ldconfig, after that try the snort -c command as mentioned above.