Perhaps, but (and this is venturing into territory where I'm making more assumption than I am restating known facts), I believe it's outside the FDA's jurisdiction to cover beverages mixed at points of purchase or in the home - I believe the former would likely fall to state health departments (or, I suppose, specific action by Congress), adn the latter jeez, I don't even know who, if anyone, would regulate that.
Again, I think this whole debate is silly, especially here in slashdot. The FDA hasn't BANNED these mixtures. What they're asking for is proof that it's safe. The FDA operates under a null hypothesis that assumes all additives are dangerous until proven otherwise (proven as GRAS). I think that's pretty reasonable when it comes to federal regulation of food and beverage products, and if it truly isn't a big deal as many commenters seem to think, then the companies can come up with the requisite evidence and caffeine as an additive in alcoholic beverages gets added to the GRAS list.
As has been laid out in detail elsewhere in the comments section, the problem isn't a matter of type -- it's a matter of degree. Most of the drinks in question are not the functional equivalent of a rum and coke. We're talking more along the lines of a no-doze with a shot of rum as a chaser.
They're basically asking the mfg's to show why it's GRAS to have that much caffeine mixed with alcohol (my guess is they won't be able to).
To everyone who is going to make a similar comment, please please please RTFA.
This has nothing to do with banning Jack & Coke, Red Bull + Vodka, etc. You're free to get smashed and caffeinated at the same time until you keel over in twitchy delirium. All the FDA has indicated is that they haven't authorized caffeine as an additive to alcoholic beverages AS THEY COME FROM THE MANUFACTURER. Well, more specifically, they're asking the makers why they thought they didn't have to clear it with the FDA.
Umm, you can revert your forwarding back to your carrier's voicemail. They'll even tell you how.
For God's sake, stop researching for a while and begin to think!