long jeans will probably suffice provided they are not the cut about type, the rule long trousers is to stop shorts, 3/4 length, etc., if they have a long trouser rule it normally goes along with no singlets [sleeved t shirts or collard shirts accepted]

We stay @ The Capo Bay Protaras and men have to wear long trousers in the restaurant but okay to wear shorts in the bar,my hubby just wears Levi jeans (smart)