PHP 5.3.0, 5.3.1 and 5.3.2 do not have SNMP support. SNMP support has restored in PHP 5.3.3.
The Windows distribution of Net-SNMP contains support files for SNMP in the
mibs directory. This directory
should be moved to DRIVE:\usr\mibs,
where DRIVE must be replaced with the driveletter where PHP is installed on,
e.g.c:\usr\mibs. Alternatively you
may set MIBDIRS environment variable pointed to your MIBs folder.
#define NO_ZEROLENGTH_COMMUNITY 1