I've been looking for this for ages:

[Iatemyskinnyperson]

A summer- weight formal coat that I can wear for weddings, etc. Found it today!!!

On phone, so hope the link works [http://www.zara.com/webapp/wcs/stores/servlet/product/ie/en/zara-S2012/190033/774007/SEAMED%2BCOAT here]

Try again;
www.zara.com/webapp/wcs/stores/servlet/product/ie/en/zara-S2012/190033/774007/SEAMED%2BCOAT

It's a lovely cream colour, nice fabric, and cheap!!! No buttons/zip, hidden pockets