Thanks! After much updating to get nmap, sniff and a few other programs running, I found that libc.so.6 (the library driftnet is now looking for) is a sym-link to libc-2.2.2.so. I would guess this is version 2.2 and nor 2.3 ;-)
The message I get now when I run driftnet is:
driftnet: /lib/libc.s0.6: version \'GLIBC_2.3\': not found (required by driftnet
From this, I\'m guessing I would need the 2.3 libraries or a version for 2.2?
Boy libraries are fun in linux... But at least after two days of searching, if anyone wants a working libpcap for the 5600, I know where to get it ;-)