Add message to iDoc status

I created Z_ functional module for inbound Sales Order iDoc processing.

I want to add my own warning message to iDoc status:

CLEAR idoc_status.

idoc_status-docnum = idoc_contrl-docnum.

idoc_status-status = '64'.

idoc_status-msgty = 'W'.

idoc_status-msgid = 'ZMSERIES'.

idoc_status-msgno = '005'.

APPEND idoc_status.

When i test in Test Tool WE19 using button "Inbound functional module" message successfully added to iDoc (WE02).

When i click "Standard inbound" - there is no my message in iDoc status.

Maybe i should use another status number? Instead of '64'?