Contrib. on behalf of organization wipes out contact subtype

I have reproduced this in the public sandbox at: http://drupal.demo.civicrm.org/

Steps to reproduce:

1) In the back-office, create an organization with a contact subtype. (I created an org called "TEST Flower Shop" of subtype "Sponsor" )

2) Create a Contribution Page that allows or requires "on behalf of" an organization. ( In the public demo this is at: http://drupal.demo.civicrm.org/civicrm/contribute/transact?reset=1&id=4 )

3) Use the contrib page from previous step to do a "on behalf of" contribution. Fill in the organization name as "TEST Flower Shop" Fill in the org. email address of the flower shop. ( The dedup rule for orgs is looking at org. name and email address, so we want to make sure these 2 fields match the existing record)

4) Look at the contact record for "TEST Flower Shop" in the back-office. It NO LONGER has any contact subtype. Its just an organization.