Oldschool Macs used colon ':' as the separator. It was not ideal for commandline use because you need to hold shift to type a colon, but in the strictly mouse oriented world of old Finder it wasn't an issue for end users.
Heh, in the Finnish layout ':' is actually the easiest of the three to type. Still requires shift but at least you don't have to reach or use both hands. The layout (like most European ones I guess) is pretty horrible for technical work of any sort, there's so much reaching to the number row while holding shift or AltGr...