diff --git a/build/macosx/mkdmg b/build/macosx/mkdmg
index b9ab8d6a5..500334bd0 100755
--- a/build/macosx/mkdmg
+++ b/build/macosx/mkdmg
@@ -42,7 +42,22 @@ echo
 
 DEVICES=`hdid -nomount $TMPFILE`
 DEVMASTER=`echo $DEVICES| awk '{ print $1 }'`
-DEVHFS=`echo $DEVICES| awk '{ print $5 }'`
+
+# Different results on 10.4 vs 10.5. Yay! [fry] 
+#echo "devices as follows"
+#echo $DEVICES
+DARWINVERSION=`uname -r`
+if [ $DARWINVERSION = "9.5.0" ] ; then 
+  DEVHFS=`echo $DEVICES| awk '{ print $3 }'`
+else 
+  if [ $DARWINVERSION = "8.11.1" ] ; then 
+    DEVHFS=`echo $DEVICES| awk '{ print $5 }'`
+  else
+    echo "This version of OS X not recognized."
+    exit;
+  fi
+fi
+
 echo Creating HFS partition $NAME on $TMPFILE at $DEVHFS
 newfs_hfs -v "$NAME" $DEVHFS
 if [ $? -ne 0 ] ; then
@@ -60,8 +75,10 @@ rm -f $TMPFILE
 exit 7
 fi
 
-DEVMASTER=`echo $DEVICES| awk '{ print $1 }'`
-DEVHFS=`echo $DEVICES| awk '{ print $5 }'`
+# These two lines removed when doing the 10.4 and 10.5 split above. 
+# They seem to be duplicates, so just rely on the earlier logic. [fry]
+#DEVMASTER=`echo $DEVICES| awk '{ print $1 }'`
+#DEVHFS=`echo $DEVICES| awk '{ print $5 }'`
 echo Copying $FOLDER to /Volumes/$NAME on $DEVMASTER
 #sudo ditto -rsrcFork "$FOLDER" "/Volumes/$NAME"
 ditto -rsrcFork "$FOLDER" "/Volumes/$NAME"