Urgent: After Upgrade Users Registering Gets "Fatal error: Call to a member function"

[ChiNa]

Dear Support, I just upgraded to 3.8.7 Level Patch 3 from 3.8.6 Level Patch1, and now when users register,

They get this error:
Fatal error: Call to a member function clean_gpc() on a non-object in /home/content/html/includes/class_dm_user.php(2963) :
eval()'d code on line 1

Same thing when I try to Add users from ADMINCP:
fatal error: Call to a member function clean_gpc() on a non-object in /home/content/html/includes/class_dm_user.php(2963) : eval()'d code on line 1

Then I went and did look in line 2963 inside class_dm_use.php, and here is the line:
($hook = vBulletinHook::fetch_hook('private_insertpm_complete')) ? eval($hook) : false;

This is a bit urgent, and my board is closed untill this is fixed and everyone is bombarding me with mails and twits. Help needed, Whats the fix, and how do I manage to get rid this error... THANK U VERY MUCH IN ADVANCE!

[Paul M]

That means you have a broken modification - one that uses the private_insertpm_complete hook.

Disable whatever Private Message modification you have installed.

[ChiNa]

Thank you sir but I got it totally at last point where I disabled all, the the 2 last one left was the "PM POP UP MESSAGING" !
But true your were right, I had it installed very long ago, but I think a part of the Upgrade it wont work, I try to reinstall and see,!
Thanks sir for a quick reply,,

- - - Updated - - -

Next day I am back to re-update, I did reinstall the new PM POP UP messaging system, and it worked out.. Thank youuuu very much