Distribution list doesn't work

I have several distribution lists (“labels”) on Google.
They appear as “groups” under my address book in EM, but, while in Google I can send to all the all Group a message, in EM it is not possible (in the field “to” [or cc, or ccn], it doesn’t appear the “auto-filling”).
I can send to a Group with EM, but without the “auto-filling” feature, just adding all the address of the group in the field “to”.
How can I do to have “auto-filling” possibility?
If I create a Distribution list, it works, but it will not be synchronised with Google.
Can you help me?