You have it backwards. NiMH cells are usually pushed
to a higher end-of-charge voltage than nicads. Charging
NiMH cells on a nicad charger will, if anything, undercharge
them.

Many NiCd chargers use a temp sensor to determine a full
charge,and that will kill NiMH.

Nicad chargers do not generally have temperature sensors, unless they're
built into the battery pack. Furthermore, a NiMH cell can tolerate higher
temperatures than a nicad so, again, a charger designed for nicads is likely
to shut off too soon rather than too later.

I worked for several months at Microsoft Hardware. One of my projects was
documenting Microsoft's rapid charger for its cordless mice. Though nicad
and NiMH cells are more alike than different, the latter are usually pushed
to higher charging cut-off voltages and temperatures. A nicad charger is not
likely to damage NiMH cells.