Without understanding what I'm doing, the following change seems to allow
the build process to continue:

=== modified file 'src/nsfns.m'
*** src/nsfns.m    2010-03-29 23:48:44 +0000
--- src/nsfns.m    2010-03-31 20:09:42 +0000
***************
*** 686,692 ****


  void
! ns_set_doc_edited (struct frame *f, Lisp_Object arg, Lisp_Object oldval)
  {
    NSView *view = FRAME_NS_VIEW (f);
    NSAutoreleasePool *pool;
--- 686,692 ----


  void
! ns_set_doc_edited (struct frame *f, Lisp_Object arg)
  {
    NSView *view = FRAME_NS_VIEW (f);
    NSAutoreleasePool *pool;