Hi,

I've used the Business Layer Generator and it has generated a rule like this for a field:

		/// <summary>
		/// Validates the Min Age
		/// </summary>
		public string ValidateMinAge(byte minAge)
		{
			string Msg = null;
			if (mmType.IsEmpty(minAge))
			{
				this.EntityPropertyDisplayName = "Minimum Age";

				Msg = this.RequiredFieldMessagePrefix + 
					this.EntityPropertyDisplayName + 
					this.RequiredFieldMessageSuffix;

				AddErrorProviderBrokenRule("MinAge",  Msg);
			}
			return Msg;
		}

This causes a zero value to be invalid. What do I do to disallow null values but allow a zero value?