PROBLEMA google maps su interfaccia

Ciao ragazzi,
nella mia applicazione ho un problema, in particolare per quanto riguarda la mappa nel file XML che descrive l'interfaccia.
In pratica se l'interfaccia è composta solamente dalla mappa, funziona correttamente, apre la mappa su tutto lo schermo:
Questo l'xml;

<?xml version="1.0" encoding="utf-8"?> <fragment xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/map" android:layout_width="match_parent" android:layout_height="match_parent" android:name="com.google.android.gms.maps.MapFragm ent"/>

se invece disegno l'interfaccia inserendo vari layout ecc e metto la mappa all'interno di un layout, l'applicazione si arresta...
Ecco l'xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_alignParentLeft="true" android:layout_alignParentTop="true" android:background="#000000" android:orientation="vertical" > <LinearLayout android:layout_width="match_parent" android:layout_height="300px" android:layout_weight="0.50" android:background="#000000" > <LinearLayout android:layout_width="250px" android:layout_height="match_parent" android:orientation="vertical" > <ScrollView android:id="@+id/scrollView1" android:layout_width="match_parent" android:layout_height="match_parent">" <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:background="#ffffff" > <Button android:id="@+id/discoveryTotaleButton" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="DISCOVERY TOTALE" /> <Button android:id="@+id/button2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> <Button android:id="@+id/button3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> <Button android:id="@+id/button4" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> <Button android:id="@+id/button5" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> <Button android:id="@+id/button6" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> <Button android:id="@+id/button7" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> <Button android:id="@+id/button8" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Button" /> </LinearLayout> </ScrollView> </LinearLayout> <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" > <fragment android:id="@+id/map" android:layout_width="match_parent" android:layout_height="match_parent" /> </LinearLayout> </LinearLayout> <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_alignParentTop="true" android:layout_weight="74.41" android:background="#345678" android:orientation="vertical" > <TextView android:id="@+id/textView2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Posizione per le info da stampare" /> </LinearLayout> </LinearLayout>

Sapete il motivo?