diff --git a/build.xml b/build.xml
index ef7b3cb..a1608ac 100644
--- a/build.xml
+++ b/build.xml
@@ -24,6 +24,10 @@
   <property name="cobertura.dir" value="${basedir}/../cobertura/"/>
   <!-- Adaptor suffix for distribution files. Useful for placing version numbers
        on our jars. -->
+  <condition property="adaptor.suffix" value="-${adaptor.version}">
+    <isset property="adaptor.version"/>
+  </condition>
+  <!-- If adaptor.version isn't set, simply use the current date. -->
   <property name="adaptor.suffix" value="-${DSTAMP}"/>
 
   <path id="adaptor.build.classpath">