Thanks for you question which I unfortunately only can answer with another question.
You write: "but i cannot write there"
Where is "there" ?
In some dialog ? what is the name ? maybe you could share a screenshot of it ?
I suppose Mirek is talking about "Property key" field in "Externalize strings" dialog window, I've just checked -- it is indeed forbidden to enter "." there.
JSF resource bundles actually support using dot(.) in property names though in JSF expression language it is considered as a special character.
So "Externalize strings" dialog should be fixed, I'll create an issue in jira.
Fixed -- dot is now supported in the dialog.
Wow I'm impressed of speed of the reaction for this issue...
Thanks very much