[Rd] trouble with accentuated characters in \title tag in Rd file

[LaurentRdevel]

Dear R-devel-list,

   Since I had no answer on the R-help-list 
(http://permalink.gmane.org/gmane.comp.lang.r.general/284539) I try to 
present my trouble on the R-devel-list. I am sure in the past (one year 
ago) to succeed in putting accentuated characters in the \title tag in a 
.Rd file. Recently, creating a package, I have NA in the title function 
instead of the text containing the accentuated character.

Could you please tell me what I missed in the understanding of package 
documentation creation ? Except the title, all works fine.

Best regards
Laurent