Inexplicable exception upon create.

Sorry! I ommited to put in the code which is as follows ...

CREATE DATABASE "C:\h\DataBase\SAPARENT.gdb" PAGE_SIZE 4096 user "SYSDBA" password "masterkey";
CREATE DOMAIN TNOTNULLID AS INTEGER NOT NULL;
CREATE DOMAIN TINT AS INTEGER;
CREATE DOMAIN GEN25_M AS VARCHAR(25) NOT NULL;
CREATE DOMAIN GEN10 AS VARCHAR(10);

CREATE TABLE SaParent(
P_NO TNOTNULLID,
PNAME GEN25_M,
PRIMARY KEY (P_NO)
);
Commit Work;

CREATE TABLE PSWRDS(
PW_NO TNOTNULLID,
P_NO TNOTNULLID CONSTRAINT VALID_UID_IN_PSWRDS REFERENCES SAPARENT(P_NO),
PW_NAME GEN25,
PRIMARY KEY (PW_NO)
);
Commit Work;

CREATE TABLE PDCTS(
PDCT_NO TNOTNULLID,
P_NO TNOTNULLID CONSTRAINT VALID_UID_IN_PDCTS REFERENCES SAPARENT(P_NO),
PDCT_NAME GEN10,
PRIMARY KEY (PDCT_NO)
);
Commit Work;

SET TERM ^ ;

CREATE TRIGGER PK_GEN_SAPARENT FOR SAPARENT
ACTIVE BEFORE INSERT POSITION 0
as
begin
new.P_NO = gen_id(PK_GEN_SAPARENT, 1);
end
^
CREATE TRIGGER PK_GEN_PSWRDS FOR PSWRDS
ACTIVE BEFORE INSERT POSITION 0
as
begin
new.PW_NO = gen_id(PK_GEN_PSWRDS, 1);
end
^
CREATE TRIGGER PK_GEN_PDCTS FOR PDCTS
ACTIVE BEFORE INSERT POSITION 0
as
begin
new.PDCT_NO = gen_id(PK_GEN_PDCTS, 1);
end
^
COMMIT WORK ^
SET TERM ; ^

SET BLOBDISPLAY 1;
SET TERM ;;
SET NAMES ;
EXIT;
SET BLOBDISPLAY 1;
SET TERM ;;
SET NAMES ;
EXIT;

The exception is

"Invalid request BLR at offset 21
generator PK_GEN_SAPARENT is not defined
Statement: CREATE TRIGGER PK_GEN_SAPARENT FOR SAPARENT
ACTIVE BEFORE INSERT POSITION 0
as
begin
new.P_NO = gen_id(PK_GEN_SAPARENT, 1);
end"

Thanks in advance.

TERRY