diff --git a/src/etc/testcases/taskdefs/optional/dotnet.xml b/src/etc/testcases/taskdefs/optional/dotnet.xml
index 1fc9c53bb..a47ae5393 100644
--- a/src/etc/testcases/taskdefs/optional/dotnet.xml
+++ b/src/etc/testcases/taskdefs/optional/dotnet.xml
@@ -110,6 +110,7 @@
       targetType="exe" 
       executable="mcs"
       includedefaultreferences="false"
+      standardlib="true"
       >
       <reference dir="/usr/lib" includes="*.dll"/>
     </csc>