Distribution system for logical system not correctly maintained

Im logged in into SAP R/3 system. When starting transaction POIT I chose "production orders for".

I fill in the fields for

Plant -> 001

Material -> T-HV200 (Ice Mix)

At the top I have to enter a "optimization system".

I chose the logical system I created (CE6CLNT850) from a list.

After I hit the execute button it says:

"Distribution system for logical system CE6CLNT850 not correctly maintained."

The distribution model for CE6CLNT850 (transaction: BD64) looks like this:

Componentsystem CE6 SAP R/3 4.6c----

CE6CLNT850

NX7CLNT800----

NX7CLNT800,No Short text exists

LOIPRO----

Production order

What is the problem here?

And by the way, WHY DO I HAVE 479 entries in my list of logical systems when I'm trying to chose the "optimization system"???

best regards,

Lunatikk