Index: trunk/packages/sipb-xen-www/code/main.py
===================================================================
--- trunk/packages/sipb-xen-www/code/main.py	(revision 428)
+++ trunk/packages/sipb-xen-www/code/main.py	(revision 429)
@@ -137,5 +137,5 @@
     name = fields.getfirst('name')
     if not validation.validMachineName(name):
-        raise InvalidInput('name', name, 'You must provide a machine name.')
+        raise InvalidInput('name', name, 'You must provide a machine name.  Max 22 chars, alnum plus \'-\' and \'_\'.')
     name = name.lower()