When exporting a Template with SNMP Items, modifying it offline and importing it again, SNMP checks fail for all SNMP Items.

I have attached two test scenarios which replicate the problem.
The _ORIG xml files are the original Templates exported. The _MODIFIED xml files contain the modification.
After importing the _MODIFIED xml files, the problem will occur.

zabbix_server.log:

Test_A zabbix_server.log:
26894:20120514:220408.548 enabling SNMP checks on host [test.example.com]: host became available
26929:20120514:220712.691 item [test.example.com:sysname.1.3.6.1.2.1.1.5.0] became not supported: : [-3] Temporary failure in name resolution

Test_B zabbix_server.log:
26894:20120514:221441.686 enabling SNMP checks on host [test.example.com]: host became available
26894:20120514:221641.722 SNMP item [sysdesc.SNMP] on host [test.example.com] failed: first network error, wait for 15 seconds
26896:20120514:221656.739 SNMP item [sysdesc.SNMP] on host [test.example.com] failed: another network error, wait for 15 seconds
26896:20120514:221711.747 SNMP item [sysdesc.SNMP] on host [test.example.com] failed: another network error, wait for 15 seconds
26896:20120514:221726.755 SNMP item [sysdesc.SNMP] on host [test.example.com] failed: another network error, wait for 15 seconds
26896:20120514:221741.775 temporarily disabling SNMP checks on host [test.example.com]: host unavailable

zabbix_server restart does not solve the problem.

Maybe some problem in the Interface code of zabbix_server?

Test_A:
Just one Item in one Template with one Host.
zbx_host_A.xml
zbx_template_A_ORIG.xml
zbx_template_A_MODIFIED.xml

Test_B:
Two Items in one Template with one Host. Only one Item will be modified.
zbx_host_B.xml
zbx_template_B_ORIG.xml
zbx_template_B_MODIFIED.xml