After installing redhat 6.1 on one of our web servers we noticed that it was not responding to requests correctly, after checking, the ip aliases for our server had not been initialized. A clean install on another system produced the same effect (after configuring the aliases using linuxconf). The quick solution for us was to copy ifup-aliases from the package that came with 6.0 (this fixed both machines) I checked to see if this had been submitted as a bug, and it doesn't seem so... which is kind of surprising... hopefully I'm not bothering you all with something that has already been brought up.
nevermind, after searching on initscripts instead of ipup-aliases I found the old bug report... sorry
*** This bug has been marked as a duplicate of 5784 ***