Folks, there's a better fix...

I ran into this issue in my own addon, and asked for help at the wowace forum.

The user Borlox gave me an effective piece of code
Code:
for i=1, STATICPOPUP_NUMDIALOGS do
  local dlg = _G["StaticPopup"..i]
  if dlg.which == "PARTY_INVITE" then
	dlg.inviteAccepted = 1
	break
  end
end

StaticPopup_Hide( "PARTY_INVITE" )
So, update the StaticPopup_Hide( "PARTY_INVITE" ) so it looks like the example above and it will work.

NOTE: It worked in my addon, but I don't use Jamba, so I can't guarantee it will work there.

Hope that helps

Please visit the official Jamba Thread for further info.