Is that MaxLength default message being created by VT or is it just using the default from the jQuery validation plugin? Originally most of the client-side vals just used the jQuery plugin defaults, and if I recall correctly the jQuery plugin does not state which field, so maybe that's at the root of this issue.
I think it makes sense to revisit all of the client-side default messages and generate our own, rather than using the plugin's default. I also agree that having the default messages in one location would make sense.
Please feel free to add issues to the issue tracker for both of these items.
Thanks,