The Zabbix SNMP agent probes don't set the community string for SNMP probes from Zabbix server running on Solaris/Sparc.

Here are the logs from snmpd in debug mode on the target host:
1) From a command-line 'snmpget' run, using 'public' as the community string. This works fine, and returns correct values to snmpget:

Received 43 bytes from 10.27.4.153
0000: 30 29 02 01 01 04 06 70 75 62 6C 69 63 A0 1C 02 0).....public?..
0016: 04 75 71 04 8E 02 01 00 02 01 00 30 0E 30 0C 06 .uq........0.0..
0032: 08 2B 06 01 02 01 01 01 00 05 00 .+.........

Received SNMP packet(s) from 10.27.4.153
GET message
– SNMPv2-MIB::sysDescr.0

Sending 89 bytes to 10.27.4.153
0000: 30 57 02 01 01 04 06 70 75 62 6C 69 63 A2 4A 02 0W.....public.J.
0016: 04 75 71 04 8E 02 01 00 02 01 00 30 3C 30 3A 06 .uq........0<0:.
0032: 08 2B 06 01 02 01 01 01 00 04 2E 53 75 6E 4F 53 .+.........SunOS
0048: 20 68 6E 75 6E 78 6A 65 74 30 31 73 20 35 2E 31 hnunxjet01s 5.1
0064: 30 20 47 65 6E 65 72 69 63 5F 31 34 31 34 31 34 0 Generic_141414
0080: 2D 30 39 20 73 75 6E 34 75 -09 sun4u

2) From a zabbix probe for the same OID, with 'public' set as the community string in the zabbix PHP frontend (the community string setting has been verified for this Item in the zabbix server's DB)

Received 37 bytes from 10.27.4.153
0000: 30 23 02 01 01 04 00 A0 1C 02 04 5A A3 33 EF 02 0#.....?...Z.3?.
0016: 01 00 02 01 00 30 0E 30 0C 06 08 2B 06 01 02 01 .....0.0...+....
0032: 01 05 00 05 00 .....

Received SNMP packet(s) from 10.27.4.153
GET message
– SNMPv2-MIB::sysName.0

Note the lack of 'public' in the SNMP GET.

Since the community string isn't sent by Zabbix, the target host doesn't respond and the Item times out after a few attempts.

I've tried Zabbix 1.8.4 and 1.8.5, and Net-SNMP 5.3, 5.6 and 5.6.1 (re-compiled each time), and all seem to be the same.