to build it on ARMv6, but you'll never get full functionality or performance. the HTC Wildfire S (which is ARMv6) has both CM9 (CDMA and GSM) and CM10 (GSM only, last time i checked). So, while it can be done, you're more or less stuck with building the kernel from scratch and hoping you can make things work, which is not fun at all.
there's some experimental builds for Wildfire on XDA for CM10. you should go check it out