Minimal vs. augmented inclusive cohortative

[Michael Daniel]

Dear all,

in most (if not all) languages there is a form or construction
expressing exhortation to a group including the speaker himself and the
addressee to perform an action together. Cf. English "Let's go!", French
"Allons!" etc.
I am looking for languages which in some way (not necessarily
inflectional!) distinguish between exhortation towards the speaker and
the addressee alone, on one hand, and towards the speaker, the
addressee, and someone else, on the other. (This is sometimes called 1st
Dual Imperative vs. 1st  Plural Imperative).
This is exemplified by Russian constructions:

Davaj    spoj-em!
PART    sing-1PL
Let's sing! [thou and me]

Davaj-te    spoj-em
PART-2PL    sing-1PL
Let's sing! [thou and me and one or more person more]

I am also very interested in knowing that such and such language
definitely _does not_ expresses this distinction in any way.

Nina Dobrushina