Comment 23 for bug 97322

For me it is the same.
I can not switch to Ad-Hoc mode with the driver rtl8187 in Ubuntu 10.04 on an amd64-platform.
It does not work using iwconfig and the network-manager is unable to do it, too.
Like koba said: it works with the driver r8187 from http://www.aircrack-ng.org/doku.php?id=r8187.
As a workaround I will use r8187.
Maybe a developer should have a look at the source from the aircrack page and see what they do differently.