Sleep mode and awake - SM=0 invalid parameter

I have tried with version 2941 to change from sleep (SM=0) to awake and returns Invalid Parameter. As some have said before in other thread, it seems this has changed. Which version do we need to use to be allowed to change from sleep to awake and vice versa?

Thanks for any response.

Just a comment for Digi.
Why is Digi changing logic functionality? This really brings issues to any development application that is built on top of the Xbee layer. We need to change logic according to the firmware.

Use the 2x21 ZB firmware use the no sleep option. This should return in the next firmware update currently in beta called 2x63.