[Dev-luatex] Problem using umlaut in hyphenation

[Jonathan Sauer]

Hello,

the following PlainTeX document produces unexpected results while
hyphenating the word "Streifzüge":

--------------------------------------------------------------------

\hyphenation{Streif-zü-ge}

Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge
Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge
Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge
Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge

Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge
Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge
Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge
Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge Streif\-zü\-ge

\showhyphens{Streifzüge}

\showhyphens{Streif\-zü\-ge}

\bye

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This is LuaTeX, Version snapshot-0.25.0-2008031419 (Web2C 7.5.6) (format=luatex 2008.3.14)  30 MAR 2008 22:29
**HyphenationProblem.tex
(HyphenationProblem.tex
Overfull \hbox (5.02353pt too wide) in paragraph at lines 5--9
\tenrm Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge 
Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge Streifzüge|

\hbox(6.94444+1.94444)x469.75499, glue set - 1.0, direction TLT
.\tenrm S
.\tenrm t
.\tenrm r
.\tenrm e
.\tenrm i
.etc.


Underfull \hbox (badness 10000) in paragraph at lines 15--15
[][] \tenrm Streifzüge

\hbox(6.94444+1.94444)x16383.99998, glue set 9793.94307, direction TLT []


Underfull \hbox (badness 10000) in paragraph at lines 17--17
[][] \tenrm Streif-zü-ge

\hbox(6.94444+1.94444)x16383.99998, glue set 9793.94307, direction TLT []

[1] )
Output written on HyphenationProblem.dvi (1 page, 1052 bytes).

--------------------------------------------------------------------

As you can see, I explicitly specify the hyphenation points for
"Streifzüge", but for some reason LuaTeX does not hyphenate it
automatically. Only when I specify the hyphenation points in the
text, does the word get hyphenated.

Am I doing something wrong?


Jonathan