"表", "予", "申", "能", "十" and "ソ" are well-known characters in Japan as trouble maker. Because '\' (0x5c) is included as a part of each multi-byte character when these characters are encoded as shift-JIS (cp932). Shift JIS (cp932) is code page of MS-Windows Japanese version.

anonymous added on 2009-09-14 03:33:02:
Wiki name error also happens with project name "あいうえお". I don't think cp932 (Shift-JIS) or the backslash/Yen character (0x5C) have nothing particular to do with the error, since Fossil is straight UTF-8 internally. -- MIURA Masahiro <echochamber at gmail>

anonymous added on 2010-01-12 07:05:05:
Happens with Russian language wiki name too:

Tried to create "Проверка" page on http://127.0.0.1:8080/wikinew. And failed:

"Проверка" is not a valid wiki page name!

anonymous added on 2010-01-12 07:08:26:
Forgot to write: Fossil version [4f24addea9] 2009-12-20 21:34:51

ron added on 2010-01-24 07:07:22:
Fixed by checkin [afe70a464686a3085141c03a1aee3eceb598ddd8]