modules partial editable by different groups?

I know how that with 'READONLY' a textfield can be set to a 'non editable' field.. but is is possible to connect this to a Usergroup.

Is there a way to get the following done:

I want a sortable module to be editable by two usergroups, but in a way that

- the first two fields can only be edited by group A and

- that field 3 and field 4 is editable by group B

It is for an orderstatusform where the ordering group can fill in an order and the manufacturing group can set the status.

example:
To prevent that the manufacturing group can edit the amount of the ordered items, it would be great if he doesnt have the rights to edit 'the other groups fields'

- - - -
some thing that does:

if usergroup = groupA;

<input type="text" name="textfield" id="textfield" value="abcde" READONLY />

if usergroup = groupB;

<input type="text" name="textfield" id="textfield" value="abcde" >