diff --git a/README.md b/README.md
index aaace18a07..a4bd9f39d5 100644
--- a/README.md
+++ b/README.md
@@ -99,10 +99,6 @@ Mac OS X
 On Mac OS X, you will need to download a set of precompiled thirdparty packages in order to
 compile Panda3D, which can be acquired from [here](https://www.panda3d.org/download/panda3d-1.9.0/panda3d-1.9.0-tools-mac.tar.gz).
 
-In order to build the installer on Mac OS X you will need to install PackageMaker.
-This can be obtained from the "Auxiliary Tools for Xcode" which can be downloaded
-from Apple [here](https://developer.apple.com/downloads/).
-
 After placing the thirdparty directory inside the panda3d source directory,
 you may build Panda3D using a command like the following:
 
diff --git a/makepanda/makepanda.py b/makepanda/makepanda.py
index 1fc89fcd46..9d6ce5531e 100755
--- a/makepanda/makepanda.py
+++ b/makepanda/makepanda.py
@@ -6844,8 +6844,9 @@ def MakeInstallerOSX():
     if PkgSkip("PYTHON")==0:     pkgs.append("pythoncode")
     if os.path.isdir("samples"): pkgs.append("samples")
     for pkg in pkgs:
+        identifier = "org.panda3d.panda3d.%s.pkg" % pkg
         plist = open("/tmp/Info_plist", "w")
-        plist.write(Info_plist % { "package_id" : "org.panda3d.panda3d.%s.pkg" % pkg, "version" : VERSION })
+        plist.write(Info_plist % { "package_id" : identifier, "version" : VERSION })
         plist.close()
         if not os.path.isdir("dstroot/" + pkg):
             os.makedirs("dstroot/" + pkg)
@@ -6855,7 +6856,12 @@ def MakeInstallerOSX():
         else:
             target = ''
 
-        if os.path.exists("/Developer/usr/bin/packagemaker"):
+        if os.path.exists("/usr/bin/pkgbuild"):
+            # This new package builder is used in Lion and above.
+            cmd = '/usr/bin/pkgbuild --identifier ' + identifier + ' --version ' + VERSION + ' --root dstroot/' + pkg + '/ dstroot/Panda3D/Panda3D.mpkg/Contents/Packages/' + pkg + '.pkg'
+
+        # In older versions, we use PackageMaker.  Apple keeps changing its location.
+        elif os.path.exists("/Developer/usr/bin/packagemaker"):
             cmd = '/Developer/usr/bin/packagemaker --info /tmp/Info_plist --version ' + VERSION + ' --out dstroot/Panda3D/Panda3D.mpkg/Contents/Packages/' + pkg + '.pkg ' + target + ' --domain system --root dstroot/' + pkg + '/ --no-relocate'
         elif os.path.exists("/Applications/Xcode.app/Contents/Applications/PackageMaker.app/Contents/MacOS/PackageMaker"):
             cmd = '/Applications/Xcode.app/Contents/Applications/PackageMaker.app/Contents/MacOS/PackageMaker --info /tmp/Info_plist --version ' + VERSION + ' --out dstroot/Panda3D/Panda3D.mpkg/Contents/Packages/' + pkg + '.pkg ' + target + ' --domain system --root dstroot/' + pkg + '/ --no-relocate'
@@ -6866,7 +6872,7 @@ def MakeInstallerOSX():
         elif os.path.exists("/Applications/PackageMaker.app/Contents/MacOS/PackageMaker"):
             cmd = '/Applications/PackageMaker.app/Contents/MacOS/PackageMaker --info /tmp/Info_plist --version ' + VERSION + ' --out dstroot/Panda3D/Panda3D.mpkg/Contents/Packages/' + pkg + '.pkg ' + target + ' --domain system --root dstroot/' + pkg + '/ --no-relocate'
         else:
-            exit("PackageMaker could not be found!")
+            exit("Neither pkgbuild nor PackageMaker could be found!")
         oscmd(cmd)
 
     if os.path.isfile("/tmp/Info_plist"):
diff --git a/panda/src/mathutil/frustum_src.I b/panda/src/mathutil/frustum_src.I
index be0bf11aee..ce1e72eebc 100644
--- a/panda/src/mathutil/frustum_src.I
+++ b/panda/src/mathutil/frustum_src.I
@@ -203,16 +203,20 @@ get_perspective_projection_mat(CoordinateSystem cs) const {
   case CS_yup_right:
     return FLOATNAME(LMatrix4)(  a, 0.0f, 0.0f, 0.0f,
                                0.0f,   e, 0.0f, 0.0f,
-                                 d,   b,  -c,-1.0f,
+                                  d,   b,  -c, -1.0f,
                                0.0f, 0.0f,   f, 0.0f);
 
   case CS_zup_left:
-    return FLOATNAME(LMatrix4)::convert_mat(CS_zup_right, CS_zup_left) *
-      get_perspective_projection_mat(CS_zup_right);
+    return FLOATNAME(LMatrix4)(  a, 0.0f, 0.0f, 0.0f,
+                               0.0f,  b,   -c, -1.0f,
+                                 d,   e,  0.0f, 0.0f,
+                               0.0f, 0.0f,   f, 0.0f);
 
   case CS_yup_left:
-    return FLOATNAME(LMatrix4)::convert_mat(CS_yup_right, CS_yup_left) *
-      get_perspective_projection_mat(CS_yup_right);
+    return FLOATNAME(LMatrix4)(  a, 0.0f, 0.0f, 0.0f,
+                               0.0f,   e, 0.0f, 0.0f,
+                                 -d,  -b,    c, 1.0f,
+                               0.0f, 0.0f,   f, 0.0f);
 
   default:
     mathutil_cat.error()
@@ -251,8 +255,10 @@ get_ortho_projection_mat(CoordinateSystem cs) const {
 */
   switch (cs) {
   case CS_zup_right:
-    return FLOATNAME(LMatrix4)::convert_mat(CS_yup_right, CS_zup_right) *
-      get_ortho_projection_mat(CS_yup_right);
+    return FLOATNAME(LMatrix4)(  a, 0.0f, 0.0f, 0.0f,
+                               0.0f, 0.0f,  -c, 0.0f,
+                               0.0f,  -b, 0.0f, 0.0f,
+                                -d,  -e,  -f, 1.0f);
 
   case CS_yup_right:
     return FLOATNAME(LMatrix4)(  a, 0.0f, 0.0f, 0.0f,
@@ -261,12 +267,16 @@ get_ortho_projection_mat(CoordinateSystem cs) const {
                                 -d,  -e,  -f, 1.0f);
 
   case CS_zup_left:
-    return FLOATNAME(LMatrix4)::convert_mat(CS_zup_right, CS_zup_left) *
-      get_ortho_projection_mat(CS_zup_right);
+    return FLOATNAME(LMatrix4)(  a, 0.0f, 0.0f, 0.0f,
+                               0.0f, 0.0f,  -c, 0.0f,
+                               0.0f,   b, 0.0f, 0.0f,
+                                -d,  -e,  -f, 1.0f);
 
   case CS_yup_left:
-    return FLOATNAME(LMatrix4)::convert_mat(CS_yup_right, CS_yup_left) *
-      get_ortho_projection_mat(CS_yup_right);
+    return FLOATNAME(LMatrix4)(  a, 0.0f, 0.0f, 0.0f,
+                               0.0f,   b, 0.0f, 0.0f,
+                               0.0f, 0.0f,   c, 0.0f,
+                                -d,  -e,  -f, 1.0f);
 
   default:
     mathutil_cat.error()