421 4.4.2 Message submission rate for this client has exceeded the configured limit

421 4.4.2 Message submission rate for this client has exceeded the configured limit

Hi

I thought this error was gone after we updated to latest version - but it is not:

421 4.4.2 Message submission rate for this client has exceeded the configured limit

Confirmed with sysadmins that configured limit is - unlimited.





What else can I check?