Oracle Database Express Edition (XE)

Hi Oracle,

I get an error when running attached script:
The error message is:
-----
ORA-00603: ORACLE server session terminated by fatal error
ORA-00600: internal error code, arguments: [kqlidchg1], [], [], [], [], [], [], [], [], [], [], []
ORA-00604: error occurred at recursive SQL level 1
ORA-00001: unique constraint (SYS.I_PLSCOPE_SIG_IDENTIFIER$) violated
00603. 00000 - "ORACLE server session terminated by fatal error"
*Cause: An ORACLE server session is in an unrecoverable state.
*Action: Login to ORACLE again so a new server session will be created
-----


-----
DROP SEQUENCE T_TEAM_ID;
DROP SEQUENCE T_COMPANY_ID;

DROP TABLE t_company CASCADE CONSTRAINTS
;
DROP TABLE t_team CASCADE CONSTRAINTS
;
CREATE TABLE t_company
(
id INTEGER NOT NULL ,
name VARCHAR2 (20) NOT NULL
)
;



ALTER TABLE t_company
ADD CONSTRAINT PK_company PRIMARY KEY ( id ) ;


CREATE TABLE t_team
(
id INTEGER NOT NULL ,
company_id INTEGER NOT NULL ,
name VARCHAR2 (20) NOT NULL
)
;



ALTER TABLE t_team
ADD CONSTRAINT PK_team PRIMARY KEY ( id ) ;



ALTER TABLE t_team
ADD CONSTRAINT FK_t_team_t_company FOREIGN KEY
(
company_id
)
REFERENCES t_company
(
id
)
;

CREATE SEQUENCE T_COMPANY_ID
NOCACHE
ORDER ;

CREATE SEQUENCE T_TEAM_ID
NOCACHE
ORDER ;

CREATE OR REPLACE TRIGGER t_team_BI
BEFORE INSERT ON t_team
FOR EACH ROW
WHEN (NEW.id IS NULL)
BEGIN
SELECT T_TEAM_ID.NEXTVAL INTO :NEW.id FROM DUAL;
END;
/

CREATE OR REPLACE TRIGGER t_company_BI
BEFORE INSERT ON t_company
FOR EACH ROW
WHEN (NEW.id IS NULL)
BEGIN
SELECT T_COMPANY_ID.NEXTVAL INTO :NEW.id FROM DUAL;
END;
/
-----
The error is thrown for the CREATE OR REPLACE TRIGGER and also comes up when creating the rest 1st, logging of and logging in again.
As it seems to be a serious error (I'd never expect it to show) and I don't now how to solve it, I wrote you this bug report.

I'm on Win7 Pro and using SQL Developer 3.0.04. Oracle version installed is:

-----
SELECT * FROM V$VERSION
where banner like 'Oracle%';
BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Express Edition Release 11.2.0.2.0 - Production
-----

Any advise or idea how to solve the error?

Thank you,
Blama