Delete character and re-using name

Hi,

I'm wondering if anyone can tell me how long it takes for a name to become available after deleting a toon? For instance, I take it that the names cross realms between Lorderon and Icecrown so I'm wondering if I delete a toon on Lorderon when would that name become available again on Icecrown?

Thanks

on Icecrown/lordaeron the name became available after server restart/crash

Names are not crossrealm, so one name can be used at same time on lordaeron and icecrown realm