XFree86 4.0 and XEmacs-21.2's configure

I recently installed XFree86-4.01 (from a contributed Mandrake RPM), and I found I could not configure 21.2 from the CVS sources, because configure detects that: #define _XOPEN_SOURCE 500 should be defined in confdefs.h, and xmkmf has the following defines: -D_POSIX_SOURCE -D_XOPEN_SOURCE this causes confdefs.h to have both: #define _XOPEN_SOURCE 500 ... #define _XOPEN_SOURCE 1 This, in turn, causes the search for X11/Intrinsic.h to fail because gcc emits the following errors: confdefs.h:67: warning: `_XOPEN_SOURCE' redefined confdefs.h:25: warning: this is the location of the previous definition I have worked around the problem for the moment by changing the definition in xmkmf to -D_XOPEN_SOURCE=500, but this problem probably needs to be fixed. Martin, what's the best way to fix this? - vin