Please Help, I got headache from this problem

Hi all, could someone help pleaseee, incoming sip calls dropped due to congestion, i have to wait for 1 or 2 minutes to get 1 call to the right place, could someone help me please, the problem seems like a bug in freepbx and here is the main information:
http://www.freepbx.org/forum/freepbx/users/potential-incorrect-handling-of-sip-404

could someone tell me how i can do the patch in the above link?

Thankssss