Module pool MP002100 with infotype 0394

Hello experts!

I have this issue.

I need to include the  ICNUM field in the view of infotype 0021 (infotype 0394 is a part of this infotype)

Campo dynpro       P0394-ICNUM

Programa           MP002100

Can you guide me in this customizing?

Overview (just infotype 0021 fields)

Infotype 0021- 0394 (Block Other; Doc no.)

T588M

Thanks in advance!!

Daniela