[Nexsys]

A spot in settins/general to place a custom greet message on the lock screen, possibly just under the time/date. i miss having my greet messages from my other phones

[blkcadi]

Pretty easy to make one for the Lockscreen, or there is a request thread here on the forum, you might get someone that could dial you in.

[StealthBravo]

Just search a little on this site and you can do it easily.

[Xevert]

It is possible but only on Jailbreakone iphones.

What you can do is make a .PNG Image in Photoshop, write the message you want and save it (make sure the size is the correct iphone dimension)

After that, download LogoMe from Cydia.

Than, SSH the picture in to the iPhone

Use LogoMe to change the loading image.

DONE.

If need more help just ask