I removed this text as it seems to be anecdotal in nature and not very helpful:
..........I am running Cacko "Heavy" on an sl-c1000. I uninstalled the 1+GB SD driver I had already installed, then rebooted, installed the SDHC driver, and rebooted again. When the system was up and running again I inserted a 4GB SDHC card and the Zaurus froze, needing a reboot to get it working properly again. That 4GB SDHC card was the only SDHC card I had to try.