Global Absence Entry Validation Formula - Error Message Numbers

Summary:

I am using system messages in the absence validation formula, synatx as below:

VALID = 'N'
ERROR_CODE = 'W'
ERROR_MESSAGE = 'HRX:::XXXX_ABS_AL_CHECK_VALID'

return VALID, ERROR_MESSAGE, ERROR_CODE


My question is:
The popup warning message on screen shows the defined message text but also shows the message number.
Is there a way of suppressing the message number? I only want the text and the Yes/No buttons to be visible.

Thanks

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