Dear Nina and Ole,

thanks Ole, for your confirmation. Masculine nouns with -uu are very
rare, and it appears that their nominative plural can be -uvo or -uno.
In An Elementary Pali Course, Ven. Narada has

1. abhibhuu > [nom. pl.] abhibhuu, abhibhuvo
2. sabba~n~nuu > sabba~n~nuu, sabba~n~nuno

In Duroiselle's grammar, there is

sayambhuu > sayambhuu, sayambhuvo

Ven. Buddhadatta has

viduu > viduu, viduno

Warder has a more complicated example:

vi~n~nuu > vi~n~nuu, vi~n~nuno, vi~n~nuuno


metta,
Yong Peng.

--- In Pali@yahoogroups.com, Ole Holten Pind wrote:

It is, indeed, nom. pl.

> If we look at "vajjabhiiruno bhavissaama", the noun and verb
> do not agree. 'vajjabhiiruno' is (dative) singular, but
> 'bhavissaama' is (first person) plural. This makes me wonder
> if 'vajjabhiiruno' is an infrequent plural form.