one more manual translation from ant's arch to osgi.arch
diff --git a/releng/build-scripts/build/run.xml b/releng/build-scripts/build/run.xml
index 8f699c0..dd2b1b5 100644
--- a/releng/build-scripts/build/run.xml
+++ b/releng/build-scripts/build/run.xml
@@ -86,6 +86,9 @@
 		<condition property="arch" value="ppc64"> <!-- HACK: hard coding 64-bit architecture -->
 			<os arch="ppc" />
 		</condition>
+		<condition property="arch" value="x86_64"> <!-- Map ant's arch to OSGi arch -->
+			<os arch="amd64" />
+		</condition>
 		<!-- if not set above, set it to os.arch -->
 		<property name="arch" value="${os.arch}" />