diff --git a/tools/build_ui.sh b/tools/build_ui.sh
index 753330f95..ace0ee3ac 100755
--- a/tools/build_ui.sh
+++ b/tools/build_ui.sh
@@ -1,6 +1,7 @@
 #!/bin/bash
 #
-# generate python files based on the designer ui files
+# generate python files based on the designer ui files. pyuic4 and pyrcc4
+# should be on the path.
 #
 
 if [ ! -d "designer" ]
@@ -11,42 +12,6 @@ fi
 
 mkdir -p aqt/forms
 
-pyuic=`which pyuic4`
-pyrcc=`which pyrcc4`
-
-if [ $? != 0 ]; then
-  if [ xDarwin = x$(uname) ]
-  then
-      if [ -e /Library/Frameworks/Python.framework/Versions/2.7/bin/pyuic4 ]
-      then
-        pyuic=/Library/Frameworks/Python.framework/Versions/2.7/bin/pyuic4
-        pyrcc=/Library/Frameworks/Python.framework/Versions/2.7/bin/pyrcc4
-      elif [ -e /opt/local/Library/Frameworks/Python.framework/Versions/2.7/bin/pyuic4 ]
-      then
-        pyuic=/opt/local/Library/Frameworks/Python.framework/Versions/2.7/bin/pyuic4
-        pyrcc=/opt/local/Library/Frameworks/Python.framework/Versions/2.7/bin/pyrcc4
-      elif [ -e /System/Library/Frameworks/Python.framework/Versions/2.6/bin/pyuic4 ]
-      then
-        pyuic=/System/Library/Frameworks/Python.framework/Versions/2.6/bin/pyuic4
-        pyrcc=/System/Library/Frameworks/Python.framework/Versions/2.6/bin/pyrcc4
-      elif [ -e /Library/Frameworks/Python.framework/Versions/2.6/bin/pyuic4 ]
-      then
-        pyuic=/Library/Frameworks/Python.framework/Versions/2.6/bin/pyuic4
-        pyrcc=/Library/Frameworks/Python.framework/Versions/2.6/bin/pyrcc4
-      elif [ -f /opt/local/Library/Frameworks/Python.framework/Versions/2.6/bin/pyuic4 ]
-      then
-        pyuic=/opt/local/Library/Frameworks/Python.framework/Versions/2.6/bin/pyuic4
-        pyrcc=/opt/local/Library/Frameworks/Python.framework/Versions/2.6/bin/pyrcc4
-      else
-        echo 'Unable to find pyuic4. If you use macports try `port install py-pyqt4`. If you use homebrew try `brew install pyqt`.'
-        exit 1
-      fi
-   else
-     echo "Unable to find pyuic4 on your path!  Please install it and try this script again."
-     exit 1
-   fi
-fi
-
 init=aqt/forms/__init__.py
 temp=aqt/forms/scratch
 rm -f $init $temp
@@ -56,21 +21,21 @@ echo "__all__ = [" >> $init
 echo "Generating forms.."
 for i in designer/*.ui
 do
-    base=$(echo $i | perl -pe 's/\.ui//; s%designer/%%;')
-    py=$(echo $i | perl -pe 's/\.ui/.py/; s%designer%aqt/forms%;')
-    echo " * "$py
-    $pyuic $i -o $py
+    base=$(basename -s.ui $i)
+    py="aqt/forms/${base}.py"
     echo "	\"$base\"," >> $init
     echo "import $base" >> $temp
-    # munge the output to use gettext
-    perl -pi.bak -e 's/QtGui.QApplication.translate\(".*?", /_(/; s/, None, QtGui.*/))/' $py
-    # remove the 'created' time, to avoid flooding the version control system
-    perl -pi.bak -e 's/^# Created:.*$//' $py
-    rm $py.bak
+    if [ $i -nt $py ]; then
+        echo " * "$py
+        pyuic4 $i -o $py
+        # munge the output to use gettext
+        perl -pi.bak -e 's/QtGui.QApplication.translate\(".*?", /_(/; s/, None, QtGui.*/))/' $py
+        rm $py.bak
+    fi
 done
 echo "]" >> $init
 cat $temp >> $init
 rm $temp
 
 echo "Building resources.."
-$pyrcc designer/icons.qrc -o aqt/forms/icons_rc.py
+pyrcc4 designer/icons.qrc -o aqt/forms/icons_rc.py