I`am alice , I am currently working with MIRACLELINUX in Japan.
We made a new patch for Windows Agent incompatible with Windows 2000 issue.
The new patch is dynamically loading Dnsapi.dll as needed using LoadLibrary() with this you don`t need to use "_WIN32_WINNT=0x0500" for fix the issue and you can enjoy the new 2.0.x feature on windows 2000.
"_WIN32_WINNT=0x0500" is too much. It affects to every code in Zabbix.
So, it's better to use dynamically loading.
The patch requires "Dnsapi.dll" in executing time for link.
We had compiled the binary in windows 2008 and tested it in windows 2000/2003/2008

We thank you for your time and would like to receive comments.