Hi again friends. I was watching in very forums about the unstability of the rtl8187 drivers for the internet connection. This is a common problem.
So, I have just seen in the Realtek's webpage a new release (2010/10/6) of the drivers for the rtl8187l devices. So I tried and found that airbase-ng didnt works neither the injection in aireplay-ng. But, the internet navigation is very stable. The new drivers employ the ieee80211 stacks and not the mac80211.
A finally point: in debian lenny (with backported amd64 kernel) after the installation of the newest drivers, when network manager tries to acquire the ip all the system freezes and I have to power off the computer. Anyone knows if someone is developing a patch or something like that?