http://www.lexneva.name/sl/search.html

That form submits searches directly to the new search system.

1. Japanes (日本語) is input to the input column.
2. Search button is pushed.

[Result]
-------------------------------------------------------------------------------
Your search - { - did not match anything we could find within Second Life. Nothing was found in Second Life containing "{". Suggestions:
Make sure all words are spelled correctly.
Try different keywords.
Try more general keywords.
-------------------------------------------------------------------------------
It was not possible to retrieve it.

1. you can see japanese "あ"(HIRAGANA LETTER A) at unicode.org
http://www.unicode.org/cgi-bin/GetUnihanData.pl?codepoint=3042
>Unihan data for U+3042
>Glyphs
>Your Browser
>あ
>Encoding Forms
>UTF-8
>E3 81 82
2. copy character from "Your Browser" column to clipboard.
3. open secondlife viewer,
open "Search Second Life" window by Ctrl+F,
select "All" tab.
4. copy character from clipboard.
press Search Button
5.you can see this message.
(note that the character code in UTF-8 of "あ" is E3 81 82)
—
Your search - FFFFE3 FFFF81 FFFF82 - did not match anything we could find within Second Life.
Nothing was found in Second Life containing "FFFFE3 FFFF81 FFFF82".

Suggestions:

• Make sure all words are spelled correctly.
• Try different keywords.
• Try more general keywords.
  —

also you can see "日","本","語" at unicode.org
"日" : UTF-8 : E6 97 A5
http://www.unicode.org/cgi-bin/GetUnihanData.pl?codepoint=65E5
"本" : UTF-8 : E6 9C AC
http://www.unicode.org/cgi-bin/GetUnihanData.pl?codepoint=672C
"語" : UTF-8 : E8 AA 9E
http://www.unicode.org/cgi-bin/GetUnihanData.pl?codepoint=8A9E

Search result in Secondlife viewer is below:
—
Your search - FFFFE6 FFFF97 FFFFA5 FFFFE6 FFFF9C FFFFAC FFFFE8 FFFFAA FFFF9E - did not match anything we could find within Second Life.
Nothing was found in Second Life containing "FFFFE6 FFFF97 FFFFA5 FFFFE6 FFFF9C FFFFAC FFFFE8 FFFFAA FFFF9E".
—

Version:
Second Life 1.18.6 (0) Dec 4 2007 18:06:16 (Second Life Release)

You are at 219535.0, 303862.0, 301.4 in karuizawa located at sim4837.agni.lindenlab.com (63.210.159.233:13006)
Second Life Server 1.18.6.75511

A retrieval word is "日","本","語".
It should be converted with %E6%97%A5%E6%9C%AC%E8%AA%9E
but if encoding is set as Shift-JIS, It is converted with %93%FA%96%7B%8C%EA

http://secondlife.com/app/search/search_proxy.php?q=%E6%97%A5%E6%9C%AC%E8%AA%9E&s=All (UTF-8)
http://secondlife.com/app/search/search_proxy.php?q=%93%FA%96%7B%8C%EA&s=All (Shift-JIS)

By the way, there seems to be a lot of people watching, but nobody voting for this... Voting helps people know to prioritize this higher, so don't forget to do both.

search_text needs to URL encoding correctly.
But the value of the range to 0x80 to 0xFF did not care
when processing each byte in URL encoding process.
Then A sign extend is the cause,
the result became strange when MSB(Most Significant Bit) is 1.
@see below:
http://en.wikipedia.org/wiki/Sign_extension
http://ja.wikipedia.org/wiki/%E7%AC%A6%E5%8F%B7%E6%8B%A1%E5%BC%B5

Example:
In the case of "char c = 0x81",
if increases the word length to 32 like "static_cast<U32>(c)"
is set to 0xFFFFFF81 and URL encoded result is not "%81" but "%FFFFFF81".

With the current source, URL encoding process is embedded in the search process.
But URL encoding process is a general-purpose process.
So, I divided the function into two.
(I wonder why "std::setw(2)" at "LLURI::escape" looks doesn't work?)

I think Sign extension is different with the CPU/OS architecture and compiler.
my environment is Core2Duo E6600 + WindowsXP Home SP2(32bit) + VC++2005 ExpressEdition.
We need the more test case.

I changed your patch slightly. The LLURI portion of the patch needs to be static_cast<S32>(static_cast<U8>(c)), otherwise some normal escaping does not work correctly.

I have changed llpaneldirfind.cpp to use LLURI::escape() and added a unit test for escaping the cedilla in Français.

Japanese searches like 日本語 appear to function as well.