Hello,
The ECLK has a fixed rate equivalent to the internal bus clock. By default, after POR, the MCU runs on internal RC oscillator and the bus clock is 6.25MHz. This is the frequency you should see on ECLK pin if enabled.
I'm not sure how there can be 41MHz, but i supose that data is invalid.
And btw, hopefully the part you use is not counterfiet.
Regards,
iggi