all TCL's clock clicks always with the -milliseconds option. The TCL manual explicitly states that without this switch the return result is platform dependant. The OpenACS code works at the millisecond granulartiy and silently assumes that 1 millisecond equals 1000 clicks which is not necessarily true.
I used this shell script to automatize the replacing:
#!/bin/bash
for file in `grep -lsr "\[clock clicks\]" /web/openacs-head/packages/ `; do echo "repairing $file" sed "s/\[clock clicks\]/\[clock clicks -milliseconds\]/g" $file > fout mv fout $file done