Language translation in module pool program

Hi,

In PO creation .change and display ( ME21N, ME22N, ME23N ) at header line there is one tab added by customization and in the subscreen of that tab there are five fields now I want to translate the language of all those five fields.

when I go se 80 >program name >doubleclick on screen number of that subscreen then >goto ->tranlation and give the target language I get the temperory list after expanding the tree I get program name there I get field which I want to translate.

out of five fields of screen which I need to translate I can see four fields there that I am able to tranlate.

My question is why I am not getting rest of one field.

Regards

Sagar