As of version 7.1 of MQ, the default security configuration is more restrictive and as such will probably need to be modified further before you can get a successful connection via a channel that has mcauser('mqm').
Refer to the WebSphere MQ documentation for further information if you still want to use the ‘mqm’ user. It is recommended that you create a new user for LAMAXU to user and apply the OAM authorities as described below.
Please replace the values below with the correct ones for your installation.
{qmgr} Queue Manager Name
{User} The MQ user being used by Lamaxu