when i`m at work i can`t install mirc because my administrator say no no no
there is a webchat where you can connect to mirc, but it works very hard because use java or not working and insert servers again and again.
A lot of peoples don`t like to install new softs for chat or they don`t know to do that, improve for the web chat to work more faster, more easy and more friendly. I think there underner should make improve because this type of chat (use web browser) will be more accessible for new users.

note:--sorry for mistakes in english--

First, it is IRC, not mIRC (mIRC is just another IRC client, much like the webchat interface you refer to). It is also possible your network administrator is blocking the standard irc port, so what you have to ask yourself is, should you really be irc'ing from work?

As far as the webchat client interface goes, If you search the web, you will find there are others available.