postgis build failing using homebrew and Mac OS X 10.7

gistfile1.diff

diff --git a/Library/Formula/postgis.rb b/Library/Formula/postgis.rb
index c1399e6..f677b8b 100644
--- a/Library/Formula/postgis.rb
+++ b/Library/Formula/postgis.rb
@@ -36,7 +36,8 @@ class Postgis < Formula
     args = [
       "--disable-dependency-tracking",
       "--prefix=#{prefix}",
-      "--with-projdir=#{HOMEBREW_PREFIX}"
+      "--with-projdir=#{HOMEBREW_PREFIX}",
+      "--with-pgconfig=#{HOMEBREW_PREFIX}/bin/pg_config"
     ]
 
     if ARGV.build_head?