PPM ITEM - PS PROJECT - ERROR

Hi,

We are working on SAP PPM 6.0. When we save the item with the 'create project' flag on, the item is saved but we get the following error:

Fiel symbol has not been assigned yet.

We've gone through all the customizing, and we are nearly sure it has nothing to do with basic customizing, such as 'Define Portfolio Item Types', 'Map Item Type to Project or PS' or 'Define Object Field Icons'.

Any idea where we should start looking...?? Any SAP note, or customizing step we may have missed??

Thanks!!!

Regards,

Anna