Recently I have met the same issue as describing at http://sourceforge.net/p/net-snmp/bugs/1946/. The problem comes from the requestid field which has been filled with the number larger than 32 bit. I am using net-snmp version 126.96.36.199.
As I see the issue stills in open status.
Would you let me know if this issue is fixed in net-snmp 188.8.131.52? If it has been fixed, would you tell me the commit-id in git repo
git://git.code.sf.net/p/net-snmp/code that fixed the issue?