Uproar at ex-UNICEF boss joining Nestle board

* Shareholders to vote Thursday on Ann Veneman joining board

* Activists urge her to refuse or set conditions

* Nestle in dock for way it markets breastmilk substitutes

* Company says appointment good for code compliance

By Stephanie Nebehay

GENEVA, April 13 (Reuters) - Former UNICEF boss Ann Veneman should refuse a seat on the board of Nestle (NESN.VX: Quote) because the food giant violates a global code on marketing of breastmilk substitute, nutrition campaign groups said on Wednesday.

UNICEF, the U.N. Children's Fund where Veneman served as executive director from 2005-2010, also sought to distance itself from the American, and said that Nestle is in breach of the 1981 code aimed at promoting breastfeeding.

Shareholders will vote on Veneman's appointment in Lausanne at Nestle's annual general meeting on Thursday. A Nestle spokesman said she would attend, but could not provide her contact details.