[AccessD] interesting problem with double lines stored in single field

You can enter two lines in a single field, and often that's convenient. For
instance, instead of requiring an Address2 field for those room numbers and
so on you'd enter them in the same field: 
 
100 First Street
<return>
Room 100
 
But these out of sight and forgotten lines cause problems when
concatenating. 
 
Run the following expression against the Northwind Employees table:
 
FullAddress: [Address] & ", " & [City] & " " & [PostalCode]
 
Three of the records return just the Address value. Those three Address
fields contain more than one line of data. 
 
I've never run into this before. I'm wondering how to work around it --
besides not storing multiple lines in the same field to begin with. 
 
Susan H.