diff -ubB old/Makefile.in new/Makefile.in
--- old/Makefile.in	2008-12-31 18:17:53.000000000 +0000
+++ new/Makefile.in	2008-12-31 18:24:10.000000000 +0000
@@ -4,7 +4,9 @@
 LDFLAGS		= @LDFLAGS@
 LIBS		= @LIBS@
 EXE		= @EXEEXT@
+ifndef SHELL
 SHELL		= /bin/ksh
+endif
 
 prefix		= @prefix@
 exec_prefix     = @exec_prefix@