change address to household retain old data

When a contact has an existing address and you update it to with an existing household address then any address fields that are blank in the new household address are not cleared in the new saved address.

For example:

Old Address
Street Address The White House
Addt'l Address 1 1600 Pennsylvania Avenue NW
Addt'l Address 2 Downtown
City Washington
Zip / Postal Code 20500
Country United States
State / Province Washington

Household address already defined
Street Address Cardboard Box
Addt'l Address 1 Under the flyover
Addt'l Address 2
City New York
Zip / Postal Code 1234
Country United States
State / Province New York

Address after assigning existing Household to a contact
Street Address Cardboard Box
Addt'l Address 1 Under the flyover
Addt'l Address 2 Downtown
City New York
Zip / Postal Code 1234
Country United States
State / Province New York

Notice that the addt'l address 2 should be blank but still shows up. This is not the expected behaviour.

Seen in 2.04 and on the sandbox.