Description of problem:
Disabled check boxes get selected on hitting the select all on Config Channel
subscriptions page

Version-Release number of selected component (if applicable): 
Rhn 500 Hosted + Satellite


How reproducible: 
Always


Steps to Reproduce:
1. Login as a user with access to atleast 2 central config channels.
2. Register a system.
3. Through the SDC, provide the system , 'provisioning' entitlement. 
4. Click Configuration -> Manage Configuration Channels -> Subscribe to Channels.
5. Select a channel or two (DO NOT select ALL channels) and hit Conitnue annd
Update on Rank Channels page.
6. Again click Configuration -> Manage Configuration Channels -> Subscribe to
Channels.
7. Notice that the previously selected check boxes are greyed out (disabled).
8. Hit the 'Select All' button.

Actual results:
All the check boxes are selected irrespective of whether they are disabled or
not. Also the pagination text shows "# selected" where # is the total number of
check boxes (Disabled + Non Disabled).

Expected results:
Only the non-disabled check boxes should be selected . Also the pagination text
should show "# selected" where # is the total number of ENABLED check boxes (Non
Disabled).