UIRT building questions

[Eelector]

I'm about to start building a UIRT2 and have some questions:

1)
Will a PIC16F84A (-04P) work or does it have to be a "non-A" version? I've heard that the A PIC is more sentitive when it comes to programming.

2)
I've got a Asus A7V133-VM motherboard. (MicroATX, Athlon or XP). WOL and WOR connectors seems to be very expencive stuff, because Asus have left them out on my board. (They are mentioned in the manual, and the soldering points are there, but no connector)
Therefor I have to use the power button method for UIRT power-on.
I don't know how my MB does this (negative or positive voltage), which pin is ground and so on.
Is there a failsafe way to do this?

3) My motherboard has an internal connector for COM2 (ribbon cable) that i intend to use for my UIRT. From the discussions on this page I've learned that the UIRT can be very sensitive when it comes to connection cables. Is there a problem with approx. 30cm of ribbon cable or will I have to choose a shielded signal cable?

thanks :)

[Luc]

1: I can't see any major differences in the datasheet wich would indicate that they are more sensitive, they should work just fine.

2: In most cases it's a negative pulse but sometimes none of the pins is really ground. I had to upgrade a Compaq PC last week, this one had a front panel with switches and led's all connected to ground, the new motherboard didn't start: I had to isolate almost everything from ground.
The best way is to use a multimeter and find out how it is done. If none of the pins is ground you have a problem.
The simplest and safest way would be to to use a 5VDC relay, the coil activated by OUT4 and the contact in parrallel with the power switch. You don't even have to know wich pin of the power connecter is the + or -. Use a type with a coil resistance > 50 ohms (max 100mA).

3: I did not experience any problems, one PC also has an internal ribbon cable and I used an unshielded extender cable of approx 1m.