*** Bug 246471 has been marked as a duplicate of this bug. ***

[packages]$ svn diff
Index: rhn_channel.pkb
===================================================================
--- rhn_channel.pkb     (revision 131533)
+++ rhn_channel.pkb     (working copy)
@@ -139,6 +139,11 @@
          FROM rhnServer
         WHERE id = server_id_in;
         
+    select current_members 
+    from rhnPrivateChannelFamily
+    where org_id = org_id_in and channel_family_id = channel_family_id_val
+    for update of current_members;
+
        available_subscriptions :=
rhn_channel.available_family_subscriptions(channel_family_id_val,
server_org_id_val);
 
        IF available_subscriptions IS NULL OR 
[packages]$ svn ci
Sending        packages/rhn_channel.pkb
Transmitting file data .
Committed revision 131673.

testplan
========
To test this, get a satellite set up so that it has exactly 1 subscription
available of the channel you want to test with.

Register 4 systems at exactly the same time.  The best way to do this is to call
up2date.py 4 times in a row from a bash script and running each command in the
background (&).

1 and exactly 1 system should get registered each time you perform the test. 
The other 3 should fail with the Error Class Code: 70  All available
subscriptions for the requested channel have been exhausted exception.

QA Verified; ran this test attempting four simultaneous registrations; the first
one works and subsequent others don't.

User jslagle's account has been closed

Using the up2date.py method verified against stage by:

* Reducing core server allocation for my org to one more than was currently used.
* Spawning 4 fake system registrations using the above method.

Result:

Only one system appeared in satellite, correct number of entitlements used in
satellite, and three error msgs on the console where the test was run.

Release pending.

5.1 Sat GA so Closed for Current Release.