vipw tries to use /usr/bin/vi, normally a link to vim, but its only there if vim-extended is installed. Also, the vipw man page mentions "vigr" but it is nowhere to be found.
First part is duplicate of bug #120.
It has been verified that the vipw man page mentions the vigr executable which is not included in the util-linux package.
1) addded vigr to util-linux-2.9-13 2) /bin/vi fix already in place