cyrus-sasl: Minor changes.

Extend m4 as it is not guaranteed to be pulled by other dependencies.
Call toochain commands with explicit path, and simplify PATH as a
result.

component/cyrus-sasl/buildout.cfg

@@ -5,6 +5,7 @@ extends =
   ../automake/buildout.cfg
   ../gdbm/buildout.cfg
   ../libtool/buildout.cfg
+  ../m4/biuldout.cfg
   ../zlib/buildout.cfg
 
 [cyrus-sasl]
@@ -13,9 +14,9 @@ url = ftp://ftp.cyrusimap.org/cyrus-sasl/cyrus-sasl-2.1.26.tar.gz
 md5sum = a7f4e5e559a0e37b3ffc438c9456e425
 location = ${buildout:parts-directory}/${:_buildout_section_name_}
 configure-command =
-  libtoolize -c -f &&
-  aclocal -I ${libtool:location}/share/aclocal -I config -I cmulocal &&
-  automake -c -a -f &&
+  "${libtool:location}/bin/libtoolize" -c -f &&
+  "${automake:location}/bin/aclocal" -I "${libtool:location}/share/aclocal" -I config -I cmulocal &&
+  "${automake:location}/bin/automake" -c -a -f &&
   ./configure
 configure-options =
   --prefix=${:location}
@@ -33,6 +34,6 @@ make-options =
   -j1
 
 environment =
-  PATH=${automake:location}/bin:${libtool:location}/bin:${m4:location}/bin:%(PATH)s
+  PATH=${m4:location}/bin:%(PATH)s
   CPPFLAGS=-fPIC -I${zlib:location}/include -I${gdbm:location}/include
   LDFLAGS=-L${zlib:location}/lib -Wl,-rpath=${zlib:location}/lib -L${gdbm:location}/lib -Wl,-rpath=${gdbm:location}/lib