Thanks for your response.  Any way in which this entry on a wish list can be
forwarded to Microsoft for an update?

The reason is simple:

Frequently my invitations involve a Dial-in number for appointments.  I have
incorporated the dial in number along with the participant code in my
signature.  However, that information is ordinarily unnecessary for routine
email messages.

I can make a signature (with no dial in) which can be the default signature
for all email messages but the appointment invitations are the ones which
have a critical need for dial-in information.  Moreover, it is not possible
to even put in signatures in a meeting invitation - unless a "new" message is
opened, the signature copied and pasted into the invitation.

As a work around, can not the use of "forms" for invitations circumvent this
shortcoming?

Thanks in advance.

Uttam