Does firebird support inner join?

I tried the query:

select count(*) as "c0" from (select distinct "T_TEMPO"."ANO" as "c0"
from "T_TEMPO" as "T_TEMPO") as "init"

but I got the following error:

"Unable to execute query, GDS Exception. Dynamic SQL Error
SQL error code = -104
Token unkown - line 1, char 31
select"

Thanks in advance
marcelo