You have to have a security code, even if its the number one.
There is a quick way of moving phones. You have to make sure TTI is turned on (second page of 'cha sys fea' as well as just under it on the same page 'Customer Telephone Activation(CTA) Enabled? Y'. Now go do a 'cha sta xxxx' on the two phones. 'X' port them (put an X in the 'port' area on the first page of the station form). Now go swap the stations physically if needed. After you plug the phone in, if you had to move it, press #*XXXX (XXXX being the ext you wish it to become).
With CTA enabled, all you ever have to remember is to 'X' port the stations in software, then plug the phone into an unused/x-ported jack and press #*(ext). Or just 'X' port them and tell the EU to take the phone label to their new location and type in #*ext. Not too many customers know about CTA and the #* feature. I think its a great feature. But the real jewel is serialized 6400 series sets. 9.2 and above remembers the serial number of the set and associates it with the ext. So if you unplug a 6400 set and on the 2nd page of the station form, you have 'Automatic moves' stroked to 'always' or 'once', you can move the phone. Kinda like having a static ip to a MAC address on a computer network.