SQL & PL/SQL

Is it possible to write in 10gR2, a MERGE statement, with UPDATE for multiple columns from a single sub_select?

like this:

MERGE INTO tableA
using ( select * from temp) tmp
on( tableA. col1 = tmp.col1)
when matched then
update set  ( tableA.col5,
                   tableA.col6, 
                   tableA.col7) = ( select sum(col2), sum(col3), sum(col5)
                                                                             from tableX 
                                                                            where tableX.col1 = tableA.col1...)