Whoever added the Makefile rule to auto-build the Grammar didn't have

his build directory in a different place than his source directory.  I
do, and it is supposed to be supported.  The naive patch caused an
endless recursion in the Make process.  This should take care of that.

Makefile.in

@@ -196,7 +196,8 @@ libpython$(VERSION).dylib: $(LIBRARY)
 $(SUBDIRS):	Makefiles
 
 Grammar:
-		cd Grammar ; $(MAKE) OPT="$(OPT)" VERSION="$(VERSION)" \
+		P=`pwd`/Parser; cd $(srcdir)/Grammar; $(MAKE) PGENDIR=$$P \
+			OPT="$(OPT)" VERSION="$(VERSION)" \
 			prefix="$(prefix)" exec_prefix="$(exec_prefix)" all
 
 Parser: