4.5: @center breaks the justification

[Akim Demaille]

Hi!

I have a slight problem with @center, which breaks the justification
of following lines in text mode:

/tmp % eof foo.texi                                               nostromo 9:57
: -------------------- foo.texi ----------------------
cat > foo.texi << \EOF
\input texinfo   @c -*-texinfo-*-
@c %**start of header
@setfilename sample.info
@settitle Sample Manual 1.0
@c %**end of header

@ifnottex
@node Top
@top GNU Sample
@end ifnottex

@menu
* First::
@end menu

@node First
@chapter First

@center This is centered on a single line.

But this long series of words, words, words, words, words, words,
words, words, words, words, words, words, words, words, words, words,
words, words, words, words, words, words, words, words, words, words,
words, words, words, words, words, words, words, words, words, words,
words, words, words, is not properly justified.

@bye
EOF
: ------------------------------------------------------------
/tmp % makeinfo --no-header foo.texi                              nostromo 9:58
GNU Sample
**********

First
*****

                  This is centered on a single line.
 But this long series of words,
words, words, words, words, words, words, words, words, words, words,
words, words, words, words, words, words, words, words, words, words,
words, words, words, words, words, words, words, words, words, words,
words, words, words, words, words, words, words, words, is not properly
justified.


Other outputs are fine.

      Thanks!