It seems to be compiling using the /usr/local/lib version. But I think the bootloader is picking up the older version (or a version otherwise without the pcap_open_live symbol). See if you can change your lib load order to pick up the /usr/local/lib (presumably the version you compiled yourself) first.

That, or see if you can get Net::Pcap to compile statically. I had some luck with this while working with disagreeable libs in win32:

    perl Makefile.PL LINKTYPE=static    # recommended
[download]

(Quoted from ExtUtils::MakeMaker.)

UPDATE/response: maybe, maybe not. Suppose there's shared versions of the lib hanging around. It's better to make sure /usr/local/lib is at the top of the libpath and to use LINKTYPE=static to make sure you're pulling in a .a instead of a .so