Although Im using SuSE since 7.2 this is my first forum post here. I just plugged in my iPhone with USB and 11.4 created an eth1 interface for the iPhone and also loads the ipheth kernel module. Anyhow I am not able to acquire an IP address using DHCP. The iPhone OS is 4.2.1 and its an iPhone 3G 8GB black.
As this is an openSUSE forum and not an iPhone forum, forgive me for not knowing to much about an iPhone. You seem to expect that the connection to the iPhone is an Etherenet one and that your iPhone is also a DHCP server. Is one or both of these assumptions correct?
the ipheth kernel module provides an ethernet device driver for iPhone tethering. Once you plug the iPhone in using USB it ifups the ehternet device for it. I think the problem is simply described here: https://bbs.archlinux.org/viewtopic.php?pid=910606
There seems to be a fix required for the ipheth kernel module in 11.4 as otherwise it might not work with iPhone devices having iOS > 4.1 installed. You’re true as it is not necessarily a pure OpenSUSE issue, but instead a kernel module problem.