When you publish or verify a product to eBay, sometimes i get error if an item contain multiple values, but ebay need only 1 value. But the problem is that sometimes i need multiple value. For example, if a book is wrote by 2 authors, i need to have 2 value, 1 for each author, so in the site i can search them separately. The best thing would be to merge the multi-value with a single value delimited by a delimiter (as "," or ";" or a delimiter that i can specify in the advanced page option). Many Thanks