Just FYI, I've checked if I can install the module on my Fedora 7 WS; works great, no problem:

All tests successful.
Files=23, Tests=591,  1 wallclock secs ( 0.56 cusr +  0.19 csys =  0.75 CPU)
make2: Leaving directory `/root/.cpanplus/5.8.8/build/NetAddr-IP-4.007/Lite/Util'
make1: Leaving directory `/root/.cpanplus/5.8.8/build/NetAddr-IP-4.007/Lite'
*** Install log written to:
  /root/.cpanplus/install-logs/NetAddr-IP-4.007-1192089244.log

Module 'NetAddr::IP' tested successfully
No errors testing all modules

You might start from the _very_ first error/warning message. You do use the CPAN or CPANPLUS module to keep your install in sync ?

Try running

perl -MCPANPLUS -e shell;

Hth.