The nethogs package is available in EPEL5, but not in EPEL4. Could nethogs be built for EL4 as well?
Lastest pkg builds fairly happily (libpcap-devel should be libpcap in EL-4)
EPEL-4 has reached end of life and is no longer supported.
Please retest your bug against EPEL-5 or EPEL-6 and re-open if the bug persists in the packages available in those releases, or file a new bug.