AVR-Chat

Quick question, I am trying to start a simple mini IR LED array but second 
guessing myself.

IR LED Info:
Forward Voltage: 1.2V (max 1.6v)
Forward Current: 100mA (max 1.2A)

I am hooking 4 LEDs direct to 12V DC power in series w/a resistor of 81ohms. 
Thing is the resistor is getting like really really hot.  I dont mean warm I 
mean hot.  Am I ok?  Second question is I want to add an additional 4 LEDs. 
Would it be better to run this like below and go w/2 X 4 LED series or move 
to 8 LEDs w/a different resistor?

I got my figures for the resistor as follows if it matters:

1.2v per LED * 4 LEDs = 4.8v drop
(12v - 4.8v drop) / (100 / 1000) = 72 ohms

Poor planning on your part does not constitute an emergency on my part.