Android: Install/uninstall scala on rooted phone. Beware! Only use this if you know what you are doing!

AndroidManifest.xml

<uses-library android:name="ch.pboos.scala-library-2.10.0"/>
<uses-library android:name="ch.pboos.scala-actors-2.10.0"/>
<uses-library android:name="ch.pboos.scala-collection-2.10.0"/>
<uses-library android:name="ch.pboos.scala-immutable-2.10.0"/>
<uses-library android:name="ch.pboos.scala-mutable-2.10.0"/>

scala-installer.sh

#!/bin/bash

# Created with information and examples from:
# https://github.com/jberkel/android-sdk-scala/blob/android-plugin/bin/createdexlibs

if [ "$ANDROID_HOME" = "" ]; then
  echo "\$ANDROID_HOME is not set. Please set it!"
  exit 1
fi

if [ "$1" = "" ] || [ "$2" = "" ]; then
  echo "Usage: ./scala-installer.sh install 2.10.0"
  echo "       ./scala-installer.sh uninstall 2.10.0"
  exit 1
fi


function android_make_system_writeable(){
  adb root
  echo "Make /system on device writable..."
  adb shell mount -o remount,rw /system
}

function android_make_system_read_only(){
  echo "Make /system on device read only again..."
  adb shell mount -o remount,ro /system
}

function unpack_actors_if_needed() {
  if [ $HAS_ACTOR_JAR -eq 0 ]; then
    echo "Unpacking scala-actors.jar..."
    ${JAR:=jar} xf $WORKING_DIR/scala-actors.jar
  fi
}


if [ "$1" = "install" ]; then
  VERSION=$2
  LINK_DOWNLOAD="http://search.maven.org/remotecontent?filepath=org/scala-lang/scala-library/$VERSION/scala-library-$VERSION.jar"
  LINK_ACTORS_DOWNLOAD="http://search.maven.org/remotecontent?filepath=org/scala-lang/scala-actors/$VERSION/scala-actors-$VERSION.jar"


  WORKING_DIR=`pwd`/scala-installer
  TMP_DIR=$WORKING_DIR/.`basename "$0"`_tmp
  JVM_LIBS_DIR=$TMP_DIR/jvm-libs
  DEX_LIBS_DIR=$WORKING_DIR/framework

  mkdir -p $JVM_LIBS_DIR/scala-library/scala \
           $JVM_LIBS_DIR/scala-collection/scala \
           $JVM_LIBS_DIR/scala-immutable/scala/collection \
           $JVM_LIBS_DIR/scala-mutable/scala/collection \
           $JVM_LIBS_DIR/scala-actors/scala \
           $DEX_LIBS_DIR

  ##########
  # Download
  ##########

  cd $WORKING_DIR
  echo "Downloading scala-library.jar..."
  curl -o scala-library.jar $LINK_DOWNLOAD

  echo "Downloading scala-actors.jar..."
  curl -o scala-actors.jar $LINK_ACTORS_DOWNLOAD
  HAS_ACTOR_JAR=$?


  ##########
  # Split up
  ##########
  DX=$ANDROID_HOME/platform-tools/dx

  ( \
    cd $JVM_LIBS_DIR/scala-library/ && \
    echo "Unpacking scala-library.jar..." && \
    ${JAR:=jar} xf $WORKING_DIR/scala-library.jar && \
    echo "Generating scala-collection.jar..." && \
    cp library.properties $JVM_LIBS_DIR/scala-collection/ && \
    cp -r META-INF $JVM_LIBS_DIR/scala-collection/ && \
    cp -r scala/collection $JVM_LIBS_DIR/scala-collection/scala/ && \
    echo "Generating scala-immutable.jar..." && \
    cp library.properties $JVM_LIBS_DIR/scala-immutable/ && \
    cp -r META-INF $JVM_LIBS_DIR/scala-immutable/ && \
    cp -r scala/collection/immutable $JVM_LIBS_DIR/scala-immutable/scala/collection/ && \
    echo "Generating scala-mutable.jar..." && \
    cp library.properties $JVM_LIBS_DIR/scala-mutable/ && \
    cp -r META-INF $JVM_LIBS_DIR/scala-mutable/ && \
    cp -r scala/collection/mutable $JVM_LIBS_DIR/scala-mutable/scala/collection/ && \
    unpack_actors_if_needed && \
    echo "Generating scala-actors.jar..." && \
    cp library.properties $JVM_LIBS_DIR/scala-actors/ && \
    cp -r scala/actors $JVM_LIBS_DIR/scala-actors/scala/ && \
    rm -rf $JVM_LIBS_DIR/scala-collection/scala/collection/immutable && \
    rm -rf $JVM_LIBS_DIR/scala-collection/scala/collection/mutable && \
    rm -rf scala/collection scala/actors \
  )

  for dir in "scala-library" "scala-collection" "scala-immutable" "scala-mutable" "scala-actors" ; do
    echo "Converting $dir.jar into a dex file..."
    ${JAR:=jar} cf $JVM_LIBS_DIR/${dir}.jar -C $JVM_LIBS_DIR/$dir .
    $DX --dex --output=$DEX_LIBS_DIR/$dir.jar $JVM_LIBS_DIR/$dir.jar
  done
  cp $JVM_LIBS_DIR/scala-library/library.properties $DEX_LIBS_DIR/

  rm -rf $TMP_DIR > /dev/null


  ###########################
  # Install on android device
  ###########################
  android_make_system_writeable

  for dir in "scala-library" "scala-collection" "scala-immutable" "scala-mutable" "scala-actors" ; do
    echo "Uploading $dir.jar to device..."
    adb push "$DEX_LIBS_DIR/$dir.jar" "/system/framework/ch.pboos.$dir-$VERSION.jar"

    TEMP_FILE=permission_tmp.xml
    PERMISSION_FILE=/system/etc/permissions/ch.pboos.$dir-$VERSION.xml
    echo "Creating $PERMISSION_FILE file on device..."
    echo "<permissions>" > $TEMP_FILE
    echo "<library name=\"ch.pboos.$dir-$VERSION\" file=\"/system/framework/ch.pboos.$dir-$VERSION.jar\" />" >> $TEMP_FILE
    echo "</permissions>" >> $TEMP_FILE

    adb push "$TEMP_FILE" "$PERMISSION_FILE"
  done

  android_make_system_read_only
  echo "Reboot your phone/tablet"
fi
if [ "$1" = "uninstall" ]; then
  echo "Uninstalling..."

  android_make_system_writeable

  echo "Removing files of version $VERSION"
  adb shell "rm /system/framework/ch.pboos.scala*$VERSION.jar"
  adb shell "rm /system/etc/permissions/ch.pboos.scala*$VERSION.xml"

  android_make_system_read_only
fi

In my system I have to change this:
DX=$ANDROID_HOME/platform-tools/dx
to this:
DX=$ANDROID_HOME/build-tools/18.1.0/dx

It corresponds to line 71.

Congratulations for your work!
In a Galaxy Mini it works only with Cyanogenmod, not with the official rooted ROM.