Author: William Joye <wjoye@cfa.harvard.edu>
Description: Add a return value to xmlrpc:serve
 This was taken from the changes in the saods9 package.
--- a/xmlrpc.tcl
+++ b/xmlrpc.tcl
@@ -86,6 +86,7 @@
 	variable	acceptfd
 
 	set acceptfd [socket -server xmlrpc::serveOnce $port]
+	return $acceptfd
 }
 
 # Accept a new connection