Application crashes as soon as I try to load Android Preference activity

The application crashes as soon as I press the settings button (set up in another layout:-). I am sharing only the relevant code here. What I want to do here is that I want to load prefs activity which has preferences setup. Any help will be highly appreciated.

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://ift.tt/nIICcg"
package="com.example.dummyproject"
android:versionCode="1"
android:versionName="1.0" >
<uses-permission android:name="android.permission.INTERNET" />

<uses-sdk
    android:minSdkVersion="11"
    android:targetSdkVersion="19" />

<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >

    <activity
        android:name=".SignIn"
        android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".Splash"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="com.example.dummyproject.start_surfing" />

            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
    </activity>

    <activity
        android:name=".Prefs"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="com.example.dummyproject.prefsettings" />

            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
    </activity>

    <activity
        android:name=".URIsettings"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="com.example.dummyproject.oldsettings" />

            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter>
    </activity>
</application>

Prefs.xml

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://ift.tt/nIICcg" >
<EditTextPreference
    android:title = "eText_ip"
    android:key = "ipAddr"
    android:summary="Enter the IP address of the webserver" 
    android:defaultValue="192.168.1.4"
    />

<EditTextPreference 
    android:title = "eText_port"
    android:key = "portNum"
    android:summary="Enter the port number on which the webserver is running"
    android:defaultValue = "8080"
    />

<EditTextPreference
    android:title="eText_location"
    android:key="location"
    android:summary = "Enter the name of .html/.php file that you want to run" 
    android:defaultValue="shaheer/traveller.php"
    />      

Prefs.java

package com.example.dummyproject;
import android.os.Bundle;
import android.preference.PreferenceFragment;

public class Prefs extends PreferenceFragment {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        addPreferencesFromResource (R.xml.prefs);
    }

}

SignIn.java

package com.example.dummyproject;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class SignIn extends Activity {
    public void onCreate (Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView (R.layout.app_login);
        // com.example.dummyproject.settings

        Button signInButton = (Button) findViewById (R.id.sign_up_btn);
        signInButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intOpenWebView = new Intent ("com.example.dummyproject.start_surfing");
                startActivity (intOpenWebView);

            }
        });

        Button settingsButton = (Button) findViewById (R.id.settings_btn);
        settingsButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // THE APPLICATION CRASHES RIGHT HERE!
                Intent intOpenWebView = new Intent ("com.example.dummyproject.prefsettings");
                startActivity (intOpenWebView);
            }
        });
    }

    private int authenticate (String userName, String password) {
        return 1;
    }
}