Using Tactical Call Signs in VMAIL

With regard to VMAIL, is there a way to change the "FROM" addresseee (Currently your Call Sign) to a Tactical Call Sign? We ran into this as an issue in a recent ECOM Drill where we were using Tactical Call Signs for Hospitals, the Red Cross and our local EOC office all manned by licensed amateur radio ops.

Currently, once you click on VMAIL the email form pops up and the FROM Box is prepopulated with your call sign, with no ability to change. Perhaps you could enable the ability to change the FORM addressee ONLY when in the EMCOMM Mode. Look forward to your reply.

Best regards and 73's

Glenn/N3COB