My husband has worn jeans, shirt and smart shoes to the restaurants and not had a problem. I don't think it's any one specific item of clothing that'll get you turned away - you just have to look smart. Us women are very lucky, we can wear pretty much what we want, as long as it's not beach wear or too revealing (e.g. see-through).
The little information brochure you get actually doesn't list no jeans on it. It says collared shirt, no shorts, and no sandals. But, like I said earlier they don't appear to be strict about it. Good to know they still let you in without the slip! The one day we had 2 of them at the pool. I thought for sure I'd loose them that day.
