Dyanmic query help

Hi,
I'm having trouble getting this stored procedure to run:

CREATE PROCEDURE FOO ( )
LANGUAGE SQL
BEGIN
DECLARE FED_NAME VARCHAR(20);
DECLARE ID INTEGER;
DECLARE END_TABLE INT DEFAULT 0;
DECLARE STMT CHAR(100);
DECLARE C1 CURSOR FOR SELECT REMOTEID, OUT_SERVERNAME||'.SYSVERSIONS' FROM BAR.BLAH WHERE REMOTEID > 1;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET END_TABLE = 1;
OPEN C1;
FETCH C1 INTO ID, FED_NAME; WHILE END_TABLE = 0 DO SET STMT = 'UPDATE NSTANFORD.FOO SET C=(SELECT VERSIONNUMBER FROM ?) WHERE A=?';
PREPARE S1 FROM STMT;
EXECUTE S1 USING FED_NAME,ID;
FETCH C1 INTO ID, FED_NAME;
END WHILE; CLOSE C1; END

This is the error message I get "An unexpected token "SELECT VERSIONNUMBER FROM" was found following "STANFORD.FOO SET C=(". Expected tokens may include: "<space>". SQLSTATE=42601"

I get this error when I call the stored procedure. Any help would be great.
Thanks.