But I noticed some bad stuff too (well, at least one item...) :
When the ethernet cable is disconnected, the CPU resets itself. This means the application is reset also and loses all of it's data. And this is something I cannot live with.
I found that the reset of the board is issued by the ephy_interrupt handler when it detects a link down. I was able to fix this by patching in the ephy_interrupt handler of CFL version 3.0, which worked. But the remaining issue is that all tasks stop working when the link is broken. I haven't figured out why that is yet, but I think this is unacceptable.
It looks like I'm going to have to stick with CFL 3.0 for now. Thanks to the information provided by bkatt, I just managed to fix all my DHCP-related problems (re-negotiating IP address after broken link returns active/becomes available...), but these fixes make no sense with CFL 3.2 if it resets the CPU when the link is broken.