When using Memory Storage Join ON Clause would not work anymore

[Zero-G. _]

Hey

I have a very curious error message.
I use mySQL 5.5.28

I use the following Select, which works alone:

SELECT DISTINCT
IF(i1.hst_code_grundglas IS NOT NULL, i1.hst_code_grundglas,
IF(i2.hst_code_grundglas IS NOT NULL, i2.hst_code_grundglas,
i3.hst_code_grundglas)) AS hst_code_grundglas,
iprooptions.phototrop,
iprooptions.hst_code_schicht
FROM iprooptions
LEFT JOIN iprocombination i2
ON (iprooptions.hst_code_schicht = i2.hst_code_schicht2
AND i2.hst_code_grundglas ='A9B'
AND i2.hst_code_schicht2 <> '******'
AND i2.lieferbarkeit = 2
AND iprooptions.manufacturer_code=i2.manufacturer_code)
LEFT JOIN iprocombination i1
ON (iprooptions.hst_code_schicht = i1.hst_code_schicht1
AND i1.hst_code_grundglas ='A9B'
AND i1.hst_code_schicht1 <> '******'
AND i1.lieferbarkeit = 2
AND iprooptions.manufacturer_code=i1.manufacturer_code)
LEFT JOIN iprocombination i3
ON (iprooptions.hst_code_schicht = i3.hst_code_schicht3
AND i3.hst_code_grundglas ='A9B'
AND i3.hst_code_schicht3 <> '******'
AND i3.lieferbarkeit = 2
AND iprooptions.manufacturer_code=i3.manufacturer_code)
WHERE iprooptions.Farbe > 0
AND (i1.hst_code_schicht1 IS NOT NULL
OR i2.hst_code_schicht2 IS NOT NULL
OR i3.hst_code_schicht3 IS NOT NULL);

Don't matter about the Select please.
My Problem is, when I now surround this select with a Create Temporary Table tmp Enginge=Memory

Then I get án error:
1 Unknown column 'iprooptions.hst_code_schicht' in 'on clause' SQL2.sql 27 3

What is this?

THX