java.lang.ClassNotFoundException: Didn't find class "android.support.multidex.MultiDexApplication"

[kdsrsl]

I refer ReadMe file and this issues(#7) to configure the project,but also ClassNotFound.
My configure:
use android-studio v0.9.2,
classpath 'com.android.tools.build:gradle:0.14.0'

main project build.gradle:

apply plugin: 'com.android.application'

android {
compileSdkVersion 21
buildToolsVersion '21.1.0'

defaultConfig {
    minSdkVersion 18
    targetSdkVersion 21
    versionCode 1
    versionName "1.0"
    multiDexEnabled true
}

buildTypes {
    debug {
        debuggable true
        runProguard false
        //applicationIdSuffix ".debug"
        proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.txt'
    }
    release {
        debuggable false
        runProguard false
        proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.txt'
    }
}

packagingOptions {
    exclude 'META-INF/DEPENDENCIES.txt'
    exclude 'META-INF/LICENSE.txt'
    exclude 'META-INF/NOTICE.txt'
    exclude 'META-INF/NOTICE'
    exclude 'META-INF/LICENSE'
    exclude 'META-INF/DEPENDENCIES'
    exclude 'META-INF/notice.txt'
    exclude 'META-INF/license.txt'
    exclude 'META-INF/dependencies.txt'
    exclude 'META-INF/LGPL2.1'
}

dexOptions {
   preDexLibraries = false
    javaMaxHeapSize "2g"
}

sourceSets {
    main {
        manifest.srcFile 'AndroidManifest.xml'
        java.srcDirs = ['src']
        resources.srcDirs = ['src']
        aidl.srcDirs = ['src']
        renderscript.srcDirs = ['src']
        res.srcDirs = ['res']
        assets.srcDirs = ['assets']
    }

    // Move the tests to tests/java, tests/res, etc...
    instrumentTest.setRoot('tests')

    // Move the build types to build-types/<type>
    // For instance, build-types/debug/java, build-types/debug/AndroidManifest.xml, ...
    // This moves them out of them default location under src/<type>/... which would
    // conflict with src/ being used by the main source set.
    // Adding new build types or product flavors should be accompanied
    // by a similar customization.
    debug.setRoot('build-types/debug')
    release.setRoot('build-types/release')
}

}

dependencies {
    compile 'com.android.support:multidex:1.0.0'
    compile fileTree(dir: 'libs', include: '*.jar')
    compile project(':photoLibrary')
    compile project(':jitsi-android-master')
    compile project(':social_sdk_library_project')
}


afterEvaluate {
    tasks.matching {
        it.name.startsWith('dex')
    }.each { dx ->
        if (dx.additionalParameters == null) {
            dx.additionalParameters = []
        }
        dx.additionalParameters += '--multi-dex' // enable multidex

        // optional
        dx.additionalParameters += "--main-dex-list=$projectDir/pathlist".toString() // enable the main-dex-list
        dx.additionalParameters += '--minimal-main-dex'
    }
}

and the pathlist file context：
android/support/multidex/BuildConfig.class
android/support/multidex/MultiDex$V14.class
android/support/multidex/MultiDex$V19.class
android/support/multidex/MultiDex$V4.class
android/support/multidex/MultiDex.class
android/support/multidex/MultiDexApplication.class
android/support/multidex/MultiDexExtractor$1.class
android/support/multidex/MultiDexExtractor.class
android/support/multidex/ZipUtil$CentralDirectory.class
android/support/multidex/ZipUtil.class

build install suss but can't run:
11-07 18:07:56.895 17564-17564/com.vcyber.cardoctor E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to instantiate application android.support.multidex.MultiDexApplication: java.lang.ClassNotFoundException: Didn't find class "android.support.multidex.MultiDexApplication" on path: /data/app/com.vcyber.cardoctor-1.apk
at android.app.LoadedApk.makeApplication(LoadedApk.java:509)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4657)
at android.app.ActivityThread.access$1400(ActivityThread.java:159)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1376)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassNotFoundException: Didn't find class "android.support.multidex.MultiDexApplication" on path: /data/app/com.vcyber.cardoctor-1.apk
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:64)
at java.lang.ClassLoader.loadClass(ClassLoader.java:501)
at java.lang.ClassLoader.loadClass(ClassLoader.java:461)
at android.app.Instrumentation.newApplication(Instrumentation.java:992)
at android.app.LoadedApk.makeApplication(LoadedApk.java:504)
            at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4657)
            at android.app.ActivityThread.access$1400(ActivityThread.java:159)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1376)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:5419)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:525)
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
            at dalvik.system.NativeStart.main(Native Method)
Thanx.

[casidiablo]

Since now Google officially support multidexing, and you are using the build tools version 21 already, please discuss this in the android-dev mailing list and/or stackoverflow as I'm not supporthing this library anymore.