No matter which ppp device I bring up (ppp0, ppp1, ppp2, etc.), ifconfig always reports that the device is ppp0. Before Red Hat v6.0 ifconfig would correctly indicate which device was actually up at the time. Now that ifconfig always reports ppp0, I cannot tell which device is actually up. This is essential information. I can find out which device is up by looking at the pid in /var/run, but I think ifconfig should correctly indicate which device is actually up, as it does for eth*, etc.
This is normal behavior. Interface names (as output by ifconfig) are always numbered sequentially starting at zero. Your interface comes up as ppp0 because it is the first ppp interface that is up on the system. The device name set in the related ifcfg-pppX file is only used to determine which copy of ppp-watch to kill in order to bring the interface down.