How did you cross compile it, and did you upload the diff back to ettercap project ? They would benefit from the changes.
I did the following to get it to work so I could execute the file from the sdcard.
# mount -o remount,rw,dirsync,nosuid,nodev,exec,relatime,uid= 1000,gid=1015,fmask=0702,dmask=0702,allow_utime=00 20,codepage=cp437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro -t vfat /dev/block/vold/179:1 /mnt/sdcard
# ./ettercap -i eth0 // // -qT -M ARP