There has been more than a little confusion surrounding the state of play with the SIM slot on Sprint’s iPhone 4S handsets. Are they unlocked? Were they unlocked? Will they ever be unlocked? We’ve gone through the whole gamut of options over the last few weeks.

SprintFeed has got hold of some clarification via internal Sprint documents, and the waters may be starting to clear. It’s a mixture of both good, and bad news.

According to their analysis of the aforementioned document, it seems that Sprint will begin locking iPhone 4S smartphones during the activation process, and that will begin on 11/11/11…

The document says that the locking process is ‘”invisible to the customer” and that it will take place during the phone’s initial activation. If we’re reading that correctly, it would mean that those with phones activated before today will have an unlocked SIM tray. Whether that will remain the case the next time they restore their iPhone, we’re not really sure, despite Sprint saying existing owners are unaffected. With iPhone’s requiring activation at each restore, we see no guarantee that Sprint couldn’t lock your SIM card slot then.

What all this boils down to is simple: Sprint clearly wants its customers to go through them when travelling abroad, and an unlocked SIM slot would mean that wouldn’t be required. If you’re lucky enough to have an unlocked handset, it may be worth trying to keep it that way!

Apple itself has said it will begin selling factory unlocked handsets some time this month, with buyers internationally already being able to pick them up. At least one member of the iDB crew is holding an unlocked iPhone 4S right now. Let’s see if you can guess which one…