MySQL Forums :: InnoDB :: ERROR 1005: Can't create table (errno: 150)

Hi!
I have read all of the inputs here regarding this 150 error, bur I cannot find a soluition to my problem. I use server version 5.0.41 and phpmyadmin version 2.10.1. The datatype of the attribute ID in the table Alternativ is the same as in the tables EttAlternativ and FleraAlternativ, IN(11) NOT NULL.The engine type is InnoDB, the three of them are not UNSIGNED and I eaven tried to create an index on the foreign key in the referencin tables. I´ll be very glad for any recomendations I can get to try.Here is my SQL statments:

Creation of table nr1:

CREATE TABLE Alternativ (FrageTypKod VARCHAR (50) NOT NULL ,
ID INT(11) NOT NULL) ENGINE=INNODB;

ALTER TABLE Alternativ ADD
CONSTRAINT PK_Alternativ
PRIMARY KEY (FrageTypKod,ID);

ALTER TABLE Alternativ ADD
CONSTRAINT FK_alternativ_fragetyp
FOREIGN KEY (FrageTypKod)
REFERENCES FrageTyp(Kod) ON UPDATE CASCADE ON DELETE CASCADE;

Cration of table nr2:
CREATE TABLE EttAlternativ (FrageTypKod VARCHAR (50) NOT NULL ,
AlternativID INT (11) NOT NULL,
SvarFrageNr INT (11) NOT NULL ,
SvarPersonRaknare INT (11) NOT NULL,
SvarOmradeNr VARCHAR (2) NOT NULL) ENGINE=INNODB;

ALTER TABLE EttAlternativ ADD
CONSTRAINT PK_EttAlternativ
PRIMARY KEY (SvarFrageNr,SvarPersonRaknare,SvarOmradeNr);

ALTER TABLE EttAlternativ ADD
CONSTRAINT FK_EttAlternativ
FOREIGN KEY (SvarFrageNr,SvarPersonRaknare,SvarOmradeNr)
REFERENCES Svar(FrageNr, PersonRaknare, OmradeNr)
ON UPDATE CASCADE ON DELETE CASCADE;

ALTER TABLE EttAlternativ ADD
CONSTRAINT FK_EttAlternativ_fragetyp
FOREIGN KEY (FrageTypKod)
REFERENCES FrageTyp(Kod) ON UPDATE CASCADE ON DELETE CASCADE;



I get the erro: 150 when I run this statment to crate an FK:

ALTER TABLE EttAlternativ ADD
CONSTRAINT FK_EttAlternativ_alt
FOREIGN KEY (AlternativID)
REFERENCES Alternativ(ID) ON UPDATE CASCADE ON DELETE CASCADE;

The erro I get is:#1005 - Can't create table '#sql-1801a_502d374.frm' (errno: 150)

Please help me see the problem...