Hyphenation patterns and Unicode

Hi everybody,
the XeTeX FAQ says that hyphenation patterns should be "true Unicode"  
files. It is not clear to me if the following (excerpt of a) file  
(for Lithuanian) is ok:

\def\ltletters{
\catcode"81=11\lccode"81="A1\uccode"81="81%A nosine
\catcode"83=11\lccode"83="A3\uccode"83="83%C su pauksteliu
\catcode"84=11\lccode"84="A4\uccode"84="84%E su tasku
% etc...
}
\ltletters
\patterns{
.ap1
.api1
.a^^b23v
%etc...
}

I would like to add this file to language.dat, rebuild all format  
files, and use LaTeX or XeLaTeX with babel. Is this expected to work?  
Or should I use the above file only for LaTeX with babel, and go for  
a different solution when I want to use XeLaTeX?

Nicola