Maybe its just me, but was looking at the on login syntax in the mirc help, but does this look right to you?:
Format: on <level>:LOGON:<commands>
Example: on 1:LOGON:/echo Logged on to server
Examples
on ^*:LOGON:*:echo Logging on to $network $server
To me, it looks liek the sytax is the example is showing an unshown parameter in the call:
on ^*:LOGON:
*:echo Logging on to $network $server
Maybe its just me?