I have Lenovo R500 and similar problem like coslinux, but I am able to establish very stable Internet connection, but when I want to check some configuration or to change it via iwconfig, no matter what is after this command (even when I'm stroke TAB), laptop freezes and power off/on only helps.
I know only one partial workaround of this problem for connecting to AP. I do simple script or another words, all configuration necessary for proper connection (essid, rate, highpower 1, iwconfig txpower... etc.) do, before ifconfig wlan0 up, then I am able to have (only with WEP or without encryption) connecion, untill I do iwconfig again and it will freeze. So I have another script witch rmmoding r8187 and ieee80211_... and other dependent modules, for the purpose of resetting card (maybe ifconfig wlan0 down also works, I don't know...) ...
Also, network-manager and wifi-radar and wlan-mon and wicd, all program which uses iwconfig or iwlist, can (on r8187 drivers) cause system freeze. So, in my script I always do:
All these problems occur of course on 2.6.32-5-686 kernel on Debian Squeeze or in newest version of most kernel in Ubuntu.
I also want to mention than on oldest kernel in Ubuntu 7.10 (2.6.24...someting) and on Debian Squeeze with 2.6.26-2-686 kernel (only rtl8187_2.6.24v3 patch applied), all works out of the box and command iwconfig can be used without any problems!
Worth mention is also that on my old Celeron PC (not laptop) the very problem also occur in the same way. So it is not problem of the hardware I guess...
I was able successful update Debian Lenny to Debian Squeeze where the very 2.6.26-2-686 kernel with r8187 driver, stay on, with me after this upgrade. So I use old kernel on newest Debian witch is fine, but come on... I want to have newest kernel because of features like possibility to use another card in my laptop witch is Intel Corporation PRO/Wireless 5100 AGN (iwlagn driver)
So... I think it can help people who wants to use this driver but can be careful and cautious using iwconfig command.
My goal is to find answer, how to compile this driver or how to workaround this problem to be able to use iwconfig command hopefully on the newest kernel...
Please don't believe people who claim that RTL8187 driver is better (on WEP or without encryption usage) than r8187 driver. Check it by yourself and feel the power of txpower