Hello,
this is my first post so far. I'm using zabbix-1.8.4 now for a while and due to some styling of my maps I experienced that the max-size of the label-field ist limited through VARCHAR(255) in dbs. Well, if you want to include in and outgoing traffic of two or more networkcards of one server in a a label you will hit this limit.
simple hack
also im wondering why these fields are not utf-8, in my opinion utf-8 would be the better solution 
have fun
this is my first post so far. I'm using zabbix-1.8.4 now for a while and due to some styling of my maps I experienced that the max-size of the label-field ist limited through VARCHAR(255) in dbs. Well, if you want to include in and outgoing traffic of two or more networkcards of one server in a a label you will hit this limit.
Code:
srv2.domain.tld
eth0: Output: {srv2.domain.tld:net.if.out[eth0,bytes].avg(300)} Input: {srv2.domain.tld:net.if.in[eth0,bytes].avg(300)}
eth1: Output : {srv2.domain.tld:net.if.out[eth1,bytes].avg(300)} Input: {srv2.domain.tld:net.if.in[eth1,bytes].avg(300)}
Code:
ALTER TABLE `sysmaps_elements` CHANGE `label` `label` TEXT CHARACTER SET latin1 COLLATE latin1_swedish_ci NOT NULL

have fun