The latest version (2.6.23.15-137 (as well as 2.6.23.14-115)) of the kernel seems to have issues with my wireless card (iwl3945). It seems to "freeze" the traffic every other minute (on the second) and stays that way for about 9 seconds. I tried downgrading the kernel to 2.6.23.9-85, which works fine, except that it adds that root hole to my system. ;-)
Sorry for not testing this before the report, but it seems that it's solved in 2.6.24.2-7 as well. Also, if it's useful for anyone, my computer is a HP Compaq 6710b Notebook.