STRICT guidelines have been issued to schools warning staff not to accept bribes from publishing companies. A stern circular was issued to principals of all schools last month listing precisely what may and may not be allowed. It updated advice sent out last year following a review of selection processes by the Independent Commission Against Corruption and came five months after the jailing of a head teacher convicted of accepting $150,000 in bribes from a publisher. While teachers may accept small gifts from pupils or parents, the Education Department told school managers there were many situations which should not be tolerated, including donations to an individual rather than to the school; holidays for teaching staff sponsored by a textbook publisher or bookseller; and the soliciting of any payment or gift. Particular care needed to be taken in relationships between principals and textbook suppliers, the circular said. ''In no circumstances may the principal suggest to a publisher or bookseller that in return for a donation or discount, a particular textbook or series of textbooks will be chosen by the school in preference to others,'' it warned. ''Schools should not allow the choice of textbooks to be in any way influenced by a donation; nor should they accept donations as a matter of course, thereby placing themselves in an obligatory position to the publisher.'' Despite the warning, the Education Department maintains that corruption involving principals and publishing firms over choice of textbooks is rare.