Time that has passed since

a user was last seen, a user joined, a question was asked, etc. currently creates problems with messages (at least in German). I think it would be better to use only digits and not names for numbers which would make things easier (perhaps this will not solely help German localisation). However I cannot find the related messages right now to see if this would be sufficient (of cause including minor modifications to these messages) to help the cause. To have a list of the respective messages would be cool. Cheers