In CYGWIN/XFree86 with a spanish keyboard.
When there is no Xserver running rxvt handles correctly
dead accents. When rxvt is attached to the Xserver it
handles incorrectly the dead accents. For example á is
written typing first the 'acute' key (nothing happens)
and then the 'a' key ('á' appears). What actually
happens is that
the 'acute' key yields immediately an acute symbol '´' and
therefore you get '´a' instead of 'á'. The same thing
happens with the other dead accents, grave, circunflex,
tilde and diaresis: you get the accent followed by the
letter. The problem is due to rxvt, not to the Xserver or
the keyboard map. Other programs such as xterm behave
correctly. I have used CYGWIN and rxvt for 2 years and
this problem has been always the same.