"accepting" events doesn't accept on server

When someone sends me an invite – whether they use iCal, Google, or whatever else – I receive an email. Opening that email, it shows that eM Client presents me with three large buttons:

Accept (green)
Tentative (grey)
Decline (red)

I will call those the “eM Client Buttons” in contrast to the fact that almost every common calendar service invite email also has built-in HTML links. They vary depending on service but, for example, Google supplies a “Going? Yes - No - Maybe” series of links. Apple has links for “Accept, Decline, Maybe”. I will call those the “Server-supplied HTML links”

So what is the problem?

Clicking the eM Client Buttons will automatically add an entry on my personal calendar but will basically never actually accept the event on the server. If I want an event organizer person to see that I’m attending, I always have to manually click the Server-supplied HTML link in the invite email.

How does eM Client create those eM Client Buttons that appear in invite emails? Would it be possible for eM Client to make a click of those buttons to also equate with clicking the Server-supplied HTML links for accept or decline?