diff --git a/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml b/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml
index be89b5f59..adcc5daf8 100644
--- a/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml
+++ b/navalplanner-business/src/test/resources/navalplanner-business-spring-config-test.xml
@@ -7,11 +7,16 @@
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
     http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd">
 
-    <!--  Data source -->
+    <!--  Data source. SingleConnectionDataSource is a fast data source (it only
+          mantains one connection which is never closed) for testing the
+          bussiness layer. It cannot be used from more than one thread in
+          parallel.
+    -->
     <bean id="dataSource"
-        class="org.springframework.jdbc.datasource.DriverManagerDataSource"
+        class="org.springframework.jdbc.datasource.SingleConnectionDataSource"
         p:driverClassName="${jdbcDriver.className}" p:url="${testDataSource.url}"
-        p:username="${testDataSource.user}" p:password="${testDataSource.password}" />
+        p:username="${testDataSource.user}" p:password="${testDataSource.password}"
+        p:suppressClose="true" />
 
 
     <!-- Hibernate Session Factory. -->