Improved Critical: Ranged Touch Attack

[Zhentil_Keep]

I'm curious as to whether the improved critical ranged touch attack actually doubles the critical range of all the spells listed under "ranged touch attack"

ex.

Orb of Force, Ray of Enfeeblement, Polar Ray, Disintegrate, lesser orb of cold etc.

I thought I read that only some spells (such as polar ray) are the only ones that will receive double damage on critical rolls... that not all the spells are coded this way.
Essentially they should all crit on a 19-20 if this feat is taken but I wanted to make sure it wasn't bugged or that it was coded before I waste a feat.

Thanks!

[Zkenic]

any ranged touch attack spell should get the 19-20 crit range, even the one that can't crit in pnp like energy drain. If there is a glitch on coding I haven't heard shout it.