Form Validation: "matches" and NOT required

[eluser]MeXHere[/eluser]
I have two fields, the second must match the first but they are not required because I use them only to update data when the user fills in that data.

The problem is that even if the second field is set with the rule "matches" to the first field and the first field is filled in with some data .. the validation passes because the second field is not required ...

:gulp:

I'm just missing something or it's just not working as expected ?