Pl/PgSQL String formatting like raise?

Hi,
is there a way in a Pl/PgSQL function (PG 8.1.* / 8.3.*) to cut together a
string value like it is done for RAISE Note/Exception?

I'd like to use s.g. like this :

StrVar := 'select * from t1 where f1=% and f2=%',
quote_literal(Param1),quote_literal(Param2);

Many Thanks!
csaba