Use of _format_ with multi step module

Is there a way to use the _format_ functionality of Contact Form 7 (as explaned here) with Multi Step Module?

[_format_{field name} “{date format}”]

For [multiform “your-dob”] I tried:
* [multiform _format_your-dob “D, d M y”]
* [multiform _format_”your-dob” “D, d M y”]
* [_format_multiform “your-dob” “D, d M y”]
* [_format_multiform your-dob “D, d M y”]
resulting in interpetation as text and displaying it as written in the form

When I tried [multiform “_format_your-dob “D, d M y””] nothing was displayed… I assume multiform was looking for a field named _format_your-dob “D, d M y” which is empty…

Thanks in advance!

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