[Android Software/Hacking General [Developers Only]] lenieto3:
Hi, thanks for the info, I made it using linux and worked really nice, these were the lines that I used, hope be useful.

This is my Android folder at home

Android/
├── eclipse
├── ndk
├── platforms-internals
├── sdk
└── tools

Start an avd running the desired API to modify in this case API-17

$ emulator -avd avd_api_17 -no-window &

Get the framework

$ cd ~/Android/
$ mkdir _framework
$ cd _framework
$ adb -s emulator-5554 pull /system/framework .

Grab BOOTCLASSPATH

$ adb -s emulator-5554 shell cat init.rc | grep BOOTCLASSPATH > bootclasspath

I didn't have the tools used in this tutorial, so I included the steps for getting them

Decompile with baskmali

$ cd ~/Android/tools
$ wget https://smali.googlecode.com/files/baksmali-1.4.2.jar
$ cd ~/Android/_framework
$ java -Xmx1024m -jar ../tools/baksmali-1.4.2.jar -a 17 -c core.jar:core-junit.jar:bouncycastle.jar:ext.jar:framework.jar:telephony-common.jar:mms-common.jar:android.policy.jar:services.jar:apache-xml.jar -x framework.odex

The parameter -a for baksmali refers to the API we are working with.

Generate out.dex with smali

$ cd ~/Android/tools
$ wget https://smali.googlecode.com/files/smali-1.4.2.jar
$ cd ~/Android/_framework
$ java -jar ../tools/smali-1.4.2.jar out

Get internal and hidden classes using dex2jar

$ cd ~/Android
$ wget https://dex2jar.googlecode.com/files/dex2jar-0.0.9.15.zip
$ unzip dex2jar-0.0.9.15.zip
$ rm dex2jar-0.0.9.15.zip
$ cd _framework/
$ ../tools/dex2jar-0.0.9.15/d2j-dex2jar.sh out.dex
$ unzip out-dex2jar.jar -d framework-classes

Add these classes to plataform's default android.jar

$ cd ~/Android
$ unzip sdk/platforms/android-17/android.jar -d custom-android
$ cp -r _framework/framework-classes/* custom-android/
$ rm -r _framework
$ cd custom-android
$ zip -r ../custom-android.jar *
$ cd ..
$ rm -r custom-android

Create new extended platform

$ cd ~/Android
$ cp -r sdk/platforms/android-17 platforms-internals/android-17-internals
$ mv custom-android.jar platforms-internals/android-17-internals/android.jar
$ vi platforms-internals/android-17-internals/build.prop

ro.build.version.release=4.2.2
ro.build.version.release=4.2.2.internal

$ ln -s ~/Android/platforms-internals/android-17-internals ~/Android/sdk/platforms/android-17-internals

I use a symlink for keep it a little organized

Hack ADT

$ cd ~/Android
$ unzip eclipse/plugins/com.android.ide.eclipse.adt_22.0.4.v201307151829--741630.jar -d hacked_adt

Go to right folder

$ cd hacked_adt/com/android/ide/eclipse/adt/internal/project/

Find file where is our desired string

$ strings -f -a -t x * | grep "android\/internal"

Edit with an hex editor

$ bless AndroidClasspathContainerInitializer.class &

Here we change the l for the x.

Replace original file making a backup

$ cd ~/Android
$ cp eclipse/plugins/com.android.ide.eclipse.adt_22.0.4.v201307151829--741630.jar eclipse/plugins/com.android.ide.eclipse.adt_22.0.4.v201307151829--741630.jar.original
$ cd hacked_adt/
$ zip -r ../eclipse/plugins/com.android.ide.eclipse.adt_22.0.4.v201307151829--741630.jar *
$ cd ..
$ rm -r hacked_adt

This worked for me... thanks E:V:A

I got just one error related to a dropbox class, but i think this is not important... hope that