Hi Jack,
Just for my understanding.
Lets call your ECC DEV SLD system A, and your portal system B.
My understanding of your scenario:
In system A SLDDSUSER gets locked in System A on example client 100.
In system B portal system when you try and send SLD data push to the SLD it says the user is locked?
If this is your scenario and my understanding is correct, I think you should try the rfc/signon_error_log parameter in you ECC DEV system. The reason I am saying this is the warning message on your Portal would just stipulate the user is locked on System A (ECC DEV) and therefore data cannot be send. However the password may be incorrectly maintained on a System C/D/E that also connect to the ECC DEV and this may be locking the user. And what your see on the Portal is just informative message.
This is my understanding of your scenario and why I think doing the trace on the portal may not help.
Please advise if my understanding of your layout is correct? And good luck in resolving the issue quickly.
Kind Regards,
Johan