Set the default PATH to the one set by login.

diff -up krb5-1.9/src/clients/ksu/Makefile.in.ksu-path krb5-1.9/src/clients/ksu/Makefile.in
--- krb5-1.9/src/clients/ksu/Makefile.in.ksu-path	2010-03-05 10:58:25.000000000 -0500
+++ krb5-1.9/src/clients/ksu/Makefile.in	2010-03-05 10:58:25.000000000 -0500
@@ -1,6 +1,6 @@
 mydir=clients$(S)ksu
 BUILDTOP=$(REL)..$(S)..
-DEFINES = -DGET_TGT_VIA_PASSWD -DPRINC_LOOK_AHEAD -DCMD_PATH='"/bin /local/bin"'
+DEFINES = -DGET_TGT_VIA_PASSWD -DPRINC_LOOK_AHEAD -DCMD_PATH='"/usr/local/sbin /usr/local/bin /sbin /usr/sbin /bin /usr/bin"'
 DEFS=
 
 PROG_LIBPATH=-L$(TOPLIBD)