diff --git a/lib/public/contacts.php b/lib/public/contacts.php
index d14806bd0c..412600dd7f 100644
--- a/lib/public/contacts.php
+++ b/lib/public/contacts.php
@@ -108,10 +108,10 @@ namespace OCP {
 		 * @return array of contacts which are arrays of key-value-pairs
 		 */
 		public static function search($pattern, $searchProperties = array(), $options = array()) {
-
 			$result = array();
 			foreach(self::$address_books as $address_book) {
-				$result = $result + $address_book->search($pattern, $searchProperties, $options);
+				$r = $address_book->search($pattern, $searchProperties, $options);
+				$result = array_merge($result, $r);
 			}
 
 			return $result;
diff --git a/tests/lib/public/contacts.php b/tests/lib/public/contacts.php
index abe0e1f625..23994667a2 100644
--- a/tests/lib/public/contacts.php
+++ b/tests/lib/public/contacts.php
@@ -41,8 +41,10 @@ class Test_Contacts extends PHPUnit_Framework_TestCase
 		// create mock for the addressbook
 		$stub = $this->getMock("SimpleAddressBook", array('getKey'));
 
-		// we expect getKey to be called once
-		$stub->expects($this->once())
+		// we expect getKey to be called twice:
+		// first time on register
+		// second time on un-register
+		$stub->expects($this->exactly(2))
 			->method('getKey');
 
 		// not enabled before register
@@ -53,11 +55,13 @@ class Test_Contacts extends PHPUnit_Framework_TestCase
 
 		// contacts api shall be enabled
 		$this->assertTrue(OCP\Contacts::isEnabled());
-	}
 
-	//
-	// TODO: test unregister
-	//
+		// unregister the address book
+		OCP\Contacts::unregisterAddressBook($stub);
+
+		// not enabled after register
+		$this->assertFalse(OCP\Contacts::isEnabled());
+	}
 
 	public function testAddressBookEnumeration() {
 		// create mock for the addressbook
@@ -76,5 +80,46 @@ class Test_Contacts extends PHPUnit_Framework_TestCase
 		$all_books = OCP\Contacts::getAddressBooks();
 
 		$this->assertEquals(1, count($all_books));
+		$this->assertEquals('A very simple Addressbook', $all_books['SIMPLE_ADDRESS_BOOK']);
+	}
+
+	public function testSearchInAddressBook() {
+		// create mock for the addressbook
+		$stub1 = $this->getMock("SimpleAddressBook1", array('getKey', 'getDisplayName', 'search'));
+		$stub2 = $this->getMock("SimpleAddressBook2", array('getKey', 'getDisplayName', 'search'));
+
+		$searchResult1 = array(
+			array('id' => 0, 'FN' => 'Frank Karlitschek', 'EMAIL' => 'a@b.c', 'GEO' => '37.386013;-122.082932'),
+			array('id' => 5, 'FN' => 'Klaas Freitag', 'EMAIL' => array('d@e.f', 'g@h.i')),
+		);
+		$searchResult2 = array(
+			array('id' => 0, 'FN' => 'Thomas Müller', 'EMAIL' => 'a@b.c'),
+			array('id' => 5, 'FN' => 'Thomas Tanghus', 'EMAIL' => array('d@e.f', 'g@h.i')),
+		);
+
+		// setup return for method calls for $stub1
+		$stub1->expects($this->any())->method('getKey')->will($this->returnValue('SIMPLE_ADDRESS_BOOK1'));
+		$stub1->expects($this->any())->method('getDisplayName')->will($this->returnValue('Address book ownCloud Inc'));
+		$stub1->expects($this->any())->method('search')->will($this->returnValue($searchResult1));
+
+		// setup return for method calls for $stub2
+		$stub2->expects($this->any())->method('getKey')->will($this->returnValue('SIMPLE_ADDRESS_BOOK2'));
+		$stub2->expects($this->any())->method('getDisplayName')->will($this->returnValue('Address book ownCloud Community'));
+		$stub2->expects($this->any())->method('search')->will($this->returnValue($searchResult2));
+
+		// register the address books
+		OCP\Contacts::registerAddressBook($stub1);
+		OCP\Contacts::registerAddressBook($stub2);
+		$all_books = OCP\Contacts::getAddressBooks();
+
+		// assert the count - doesn't hurt
+		$this->assertEquals(2, count($all_books));
+
+		// perform the search
+		$result = OCP\Contacts::search('x', array());
+
+		// we expect 4 hits
+		$this->assertEquals(4, count($result));
+
 	}
 }