Additional Settings For Custom Profile Fields [1.2]

[anori]

I have been wondering is there a way to make a x amount of fields pop up below each other?
Lets say you fill in field 1 field 2 appears, without having to create x amount of fields?
Currently i want to do something like this so:

[Select box] [textbox] [textbox]

And would like that to automatically offer another one like that each time the person fills in the 3.