gvim thinks that a Japanese star is a signle width character, whereas in fact it is a double width character in Koichi fonts. Note that gnome-terminal forces the star into single cell, and so regular tty mode vim works fine. It looks quite ugly though. Mozilla shows normal double-width star. To reproduce, visit any webpage with star (it's on every other Japanese webpage, and I'm going to attach a test file). Select and paste into gvim, observe the fancy effects when cursor starts flashing :-) The UTF-8 code for the character is 0xe29885 in big-endian (byte stream).
Created attachment 102777 [details] File with star (UTF-8)
Fedora Core 2 is now maintained by the Fedora Legacy project for security updates only. If this problem is a security issue, please reopen and reassign to the Fedora Legacy product. If it is not a security issue and hasn't been resolved in the current FC3 updates or in the FC4 test release, reopen and change the version to match.
This seems to work in FC4T2 with vim-X11-6.3.067-1. Although the fix was to treat the star as a single cell character. Eww...