Can you charge a NIMH battery with a trickle charge NiCad battery charger
The reccomended trickle charge current for most NiMH batteries is C/20  but for NiCd's it;s C/10

However NiMH typically has twice the capacitoy of similarly sized NiCd so the current comes out about right. So yes, you can use a NiCd trickle charger on NiMH cells.

Don't try to use a fast charger though, the NiMH voltage profile is different and the cells will be damaged.