when you check the box, the revision is used at which those externals currently are at. Because that's the current state. Why would you need another revision?
-- You received this message because you are subscribed to the Google Groups "TortoiseSVN" group. To unsubscribe from this group and stop receiving emails from it, send an email to tortoisesvn+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/tortoisesvn/76f8abd4-8759-4f69-8a29-9f14cf8cf79bn%40googlegroups.com.
