I would like to propose to change the way that ZABBIX_SENDER handles the "-s" option. Right now, it's case sensitive. I would like to see it as case insensitive. I read some users problems in the forum (including myself) that was related with the fact that the hostname was registered using capital characteres, but when using zabbix_sender, by mistake they used "normal" ones (such as ZABBIX SERVER and ZABBIX Server).

I can't think about any security issues releted with this change.