// Works correctly
em.createQuery("SELECT s FROM Simple s WHERE :ram < s.maxRam")
				.setParameter("ram", 2.0)
				.getResultList();

// Works correctly
em.createQuery("SELECT :ram FROM Simple s WHERE :ram2 < s.maxRam")
				.setParameter("ram", 2.0)
				.setParameter("ram2", 2.0)
				.getResultList();
				
// Throws the described exception
em.createQuery("SELECT :ram FROM Simple s WHERE :ram < s.maxRam")
				.setParameter("ram", 2.0)
				.getResultList();