X11-related builds fail on Darwin

["Pouya D. Tafti" <p.d.tafti%gmail.com@localhost>]

After a recent pkgsrc update, I started having problems building
X11-related packages on Darwin (this is on a Snow Leopard 10.6.2 box,
and I hadn't updated pkgsrc for quite a while).  With a fresh
reinstall of pkgsrc-2010Q1, builds of X11 apps still invariably fail
with something like:

CC dmenu.c
In file included from dmenu.c:11:
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:337: error:
expected specifier-qualifier-list before 'Cursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:1577: error:
expected '=', ',', ';', 'asm' or '__attribute__' before
'XCreatePixmapCursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:1586: error:
expected '=', ',', ';', 'asm' or '__attribute__' before
'XCreateGlyphCursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:1595: error:
expected '=', ',', ';', 'asm' or '__attribute__' before
'XCreateFontCursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:2052: error:
expected declaration specifiers or '...' before 'Cursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:2252: error:
expected declaration specifiers or '...' before 'Cursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:2553: error:
expected declaration specifiers or '...' before 'Cursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:2725: error:
expected declaration specifiers or '...' before 'Cursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:2755: error:
expected declaration specifiers or '...' before 'Cursor'
/usr/pkgsrc/x11/dmenu/work/.buildlink/include/X11/Xlib.h:3080: error:
expected declaration specifiers or '...' before 'Cursor'
*** [dmenu.o] Error code 1
1 error

Any ideas why?

Thanks,
Pouya