In version 2.03, has been added a new verification in agent to limit the maximum size of packets to 128MB. I have a agent that has only a few items of active checks (less than 10), and yet the message size limit is alarmed in the log. Items are checking the operating system and return numeric values??. I think it may be a bug in relation to zabbix or operating system.
To circumvent this problem, the ideal would be to create a new parameter in the agent to change this maximum message size, which is currently fixed in the source code at 128MB.