buddypress and multisite - display issue on new blog creation

[sjoannef]

The new blog url shows
​http://TEXTBOX.http://mydomain.com

Before installing buddypress, this correctly showed
​http://TEXTBOX.mydomain.com

I googled a bit and found other sites that appear to have this issue. Example:
​http://visualsociety.com/register/
(click the "Yes, I'd like to create a new site" checkbox to see the issue)

A spotcheck shows that the few sites I clicked on that had this problem all had buddypress.

[mercime]

BP 1.5.1 Registration

[mercime]

When the Super Admin enables registration and new users fill up the Registration Form for a subdomain installation, it's confirmed that what shows up under "Blog URL (required)" is per image attached:

http://___input-area____ . http://yoursite.com/

However, the subdomain site URL generated is what it should be when user submits registration.
e.g. Enter buddypress in input-area and you get ​http://buddypress.yoursite.com/

The correct subdomain URL ​http://buddypress.yoursite.com is posted in the activation email sent to user as well. All other subdomain sites created before BuddyPress was installed are still showing the correct subdomain URL's.

Putting the BP registration form error aside, something else is interfering with the generation of correct subdomain URL's for OP sites.

[boonebgorges]

Duplicate of #3684