diff --git a/plugins/python-build/bin/python-build b/plugins/python-build/bin/python-build
index 4f5871aa..8561bfca 100755
--- a/plugins/python-build/bin/python-build
+++ b/plugins/python-build/bin/python-build
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-PYTHON_BUILD_VERSION="20140204"
+PYTHON_BUILD_VERSION="20140225"
 
 set -E
 exec 3<&2 # preserve original stderr at fd 3
@@ -65,6 +65,12 @@ sanitize() {
   printf "%s" "$1" | sed "s/[^A-Za-z0-9.-]/_/g; s/__*/_/g"
 }
 
+colorize() {
+  if [ -t 1 ]; then printf "\e[%sm%s\e[m" "$1" "$2"
+  else echo -n "$2"
+  fi
+}
+
 build_failed() {
   { echo
     echo "BUILD FAILED"
@@ -666,15 +672,35 @@ build_package_jruby() {
   build_package_copy
   cd "${PREFIX_PATH}/bin"
   ln -fs jruby ruby
+  chmod +x ruby
   install_jruby_launcher
   remove_windows_files
   fix_jruby_shebangs
 }
 
+graal_architecture() {
+  if [ "$(uname -m)" != "x86_64" ]; then
+    echo "no nightly builds available" >&2
+    exit 1
+  fi
+
+  case "$(uname -s)" in
+  "Darwin") echo "macosx-x86_64";;
+  "Linux") echo "linux-x86_64";;
+  *)
+    echo "no nightly builds available" >&2
+    exit 1;;
+  esac
+}
+
 install_jruby_launcher() {
-  cd "${PREFIX_PATH}/bin"
-  { ./ruby gem install jruby-launcher
-  } >&4 2>&1
+  # If this version of JRuby has been modified for Graal, don't overwrite the
+  # launcher scripts
+  if ! grep -q graalvm "${PREFIX_PATH}/bin/jruby"; then
+    cd "${PREFIX_PATH}/bin"
+    { ./ruby gem install jruby-launcher
+    } >&4 2>&1
+  fi
 }
 
 fix_jruby_shebangs() {
@@ -806,19 +832,29 @@ fix_rbx_irb() {
     true
 }
 
+require_java7() {
+  local version="$(java -version 2>&1 | head -1)"
+  if [[ $version != *1.[789]* ]]; then
+    colorize 1 "ERROR" >&3
+    echo ": Java 7 required. Please install a 1.7-compatible JRE." >&3
+    return 1
+  fi
+}
+
 require_gcc() {
   local gcc="$(locate_gcc || true)"
 
   if [ -z "$gcc" ]; then
-    local esc=$'\033'
     { echo
-      echo "${esc}[1mERROR${esc}[0m: This package must be compiled with GCC, but python-build couldn't"
+      colorize 1 "ERROR"
+      echo ": This package must be compiled with GCC, but python-build couldn't"
       echo "find a suitable \`gcc\` executable on your system. Please install GCC"
       echo "and try again."
       echo
 
       if [ "$(uname -s)" = "Darwin" ]; then
-        echo "${esc}[1mDETAILS${esc}[0m: Apple no longer includes the official GCC compiler with Xcode"
+        colorize 1 "DETAILS"
+        echo ": Apple no longer includes the official GCC compiler with Xcode"
         echo "as of version 4.2. Instead, the \`gcc\` executable is a symlink to"
         echo "\`llvm-gcc\`, a modified version of GCC which outputs LLVM bytecode."
         echo
@@ -828,14 +864,18 @@ require_gcc() {
         echo "GCC compiler installed on your system."
         echo
 
+        colorize 1 "TO FIX THE PROBLEM"
         if type brew &>/dev/null; then
-          echo "${esc}[1mTO FIX THE PROBLEM${esc}[0m: Install Homebrew's apple-gcc42 package with this"
-          echo "command: ${esc}[4mbrew tap homebrew/dupes ; brew install apple-gcc42${esc}[0m"
+          echo ": Install Homebrew's apple-gcc42 package with this"
+          echo -n "command: "
+          colorize 4 "brew tap homebrew/dupes ; brew install apple-gcc42"
         else
-          echo "${esc}[1mTO FIX THE PROBLEM${esc}[0m: Install the official GCC compiler using these"
-          echo "packages: ${esc}[4mhttps://github.com/kennethreitz/osx-gcc-installer/downloads${esc}[0m"
+          echo ": Install the official GCC compiler using these"
+          echo -n "packages: "
+          colorize 4 "https://github.com/kennethreitz/osx-gcc-installer/downloads"
         fi
 
+        echo
         echo
         echo "You will need to install the official GCC compiler to build newer"
         echo "versions of CPython even if you have installed Apple's Command Line Tools"
@@ -1299,7 +1339,7 @@ done
 DEFINITION_PATH="${ARGUMENTS[0]}"
 if [ -z "$DEFINITION_PATH" ]; then
   usage
-elif [ ! -e "$DEFINITION_PATH" ]; then
+elif [ ! -f "$DEFINITION_PATH" ]; then
   BUILTIN_DEFINITION_PATH="${PYTHON_BUILD_ROOT}/share/python-build/${DEFINITION_PATH}"
   if [ -e "$BUILTIN_DEFINITION_PATH" ]; then
     DEFINITION_PATH="$BUILTIN_DEFINITION_PATH"