the drivers are buggy on xp 32bit at least, I got BSOD with ie. puttytel.exe BUGCODEUSB
that was on a physical machine, if you use them inside a VirtualPC in XP Mode software made by Microsoft then you may never get any BSOD or hangs, already tested them for some days now.
Note though that vmware workstation and virtualbox, while both can do virtual machines, I tried both xp and ubuntu (both 32bit) inside a windows 7 64bit and they didn't work, only XP Mode worked with my CA-42 cable and putty or bray's terminal; in those two I couldn't send/receive although drivers installed ok;
hope this helps bye