Record Level Filters Problem

Danio_AB

Hello,
Im using NAV 4 SP3 right now, and my company want to implement a different model of security... some users will have access to create items in one range, and documents of certain type (quotes). For example, users that create quotes have to put on that documents items wich we don't have yet. So, they need to open item cards for that items. I want that items to be in one range (we are using table 310 (No. Series Relationship) to keep this (items created by them are coding like PO***). In case that the quote will be transformed in sales command, we manually replace the PO*** code with another...
I try to implement this by putting record filters on table 308 (somthing like ART|PO|V_OFFER...) and, i can create items (with PO numbering), but when i went to create quote document, it says that i don't have permissions to access table 308 (in role definition i have:

Object Type Object ID Object Name Read Permission Insert Permission Modify Permission Delete Permission Execute Permission Security Filter
Table Data 308 No. Series Yes Yes No. Series: Code=ART|PO|TA|V_OFER|V_OFFER|VS

Thanks in advance...
Dan