Googling around looks like the this is what it needs to work. http://acx100.sourceforge.net
. Never used it so no help as far as install goes but if it is like any of the other modules like madwifi, ndiswrapper, and others then you will need to install the matching kernel-devel.*.rpm that matches the kernel.
Other option is to use the Windows driver with the ndiswrapper modules. If using precompiled kernel rpms then goto http://www.atrpms.net/
and get an rpm version that matches your exact kernel version ready to install.
Distribution: RHEL 5.1 with Pieces of this and that.
Kernel 184.108.40.206, KDE 3.5.8 and KDE 4.0 beta, Plus Development src.rpm, ATI fglrx64_7_1_0-8.433-1 rpm with 3D and DRI working.
Acer 5100-5840 with webcam, ati, sdcard reader, sound, atheros based wireless, all working. Only thing not working is the memory stick reader.