Admob Banner not showing “Tabhost and Webview”

[RinsVeili]

The program is basically a TabHost with a webview in each Tabs (3 Tabs at the moment).The problem is that: the banner of admob is "below" every webview. I can see the banner when the URL of each webview is charging, but then, the web page overlaps it.code is here:\[code\]<?xml version="1.0" encoding="utf-8"?><TabHost xmlns:android="http://schemas.android.com/apk/res/android"xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"android:id="@android:id/tabhost"android:layout_width="match_parent"android:layout_height="match_parent"><LinearLayoutandroid:id="@+id/banner"android:layout_width="fill_parent"android:layout_height="wrap_content"android:layout_gravity="bottom"androidrientation="vertical" /><LinearLayoutandroid:layout_width="match_parent"android:layout_height="match_parent"androidrientation="vertical" ><TabWidgetandroid:id="@android:id/tabs"android:layout_width="match_parent"android:layout_height="wrap_content" /><FrameLayout android:id="@android:id/tabcontent" android:layout_width="match_parent" android:layout_height="wrap_content"> <WebView android:id="@+id/webView1" android:layout_width="match_parent" android:layout_height="wrap_content" /> <WebView android:id="@+id/webView2" android:layout_width="match_parent" android:layout_height="wrap_content" /> <WebView android:id="@+id/webView3" android:layout_width="match_parent" android:layout_height="wrap_content" /> </FrameLayout> </LinearLayout> </TabHost>\[/code\]How can i fix it? thanks in advance