diff --git a/build-common.xml b/build-common.xml
index a7e4270fee02087e17ec499c98026e07ec92c720..1715419aeb1b8ba1fd2bec762809efbfc2da8126 100644
--- a/build-common.xml
+++ b/build-common.xml
@@ -24,7 +24,7 @@
 	</target>
 	<target name='compile'>
 		<mkdir dir='build'/>
-		<javac srcdir='net/sf/briar' destdir='build'
+		<javac srcdir='net/sf/briar' destdir='build' source='1.5'
 			includeantruntime='false'>
 			<classpath>
 				<fileset refid='bundled-jars'/>
diff --git a/test/build.xml b/test/build.xml
index 17dd1da67a7f0693cfd41abd1628f8a4131e8311..f5f8413e0f4be0e11ef2e910c1473d709a8049be 100644
--- a/test/build.xml
+++ b/test/build.xml
@@ -1,7 +1,10 @@
 <project name='test' default='test'>
 	<import file='../build-common.xml'/>
 	<target name='test' depends='depend'>
-		<junit printsummary='on' showoutput='true'>
+		<junit printsummary='on' showoutput='true' fork='yes' forkmode='once'>
+			<assertions>
+				<enable/>
+			</assertions>
 			<classpath>
 				<fileset refid='bundled-jars'/>
 				<fileset refid='test-jars'/>