Not sure what the howto says, but here is a page, unless you already have it, that has some detailed Lucent LT installation help. Most winmodems don't have a chance in Linux altogether, but it's possible. Check here
and see if it helps any. It depends on what kernel you are using also. You can tell by after booting, the console will say something like Running Kernel 2.x.x. Hope this gave you some help. I'm not familiar with red hat so this is all i found.