USE @ on user name on ISPConfig

[albertix]

I hava a IspConfig and it work perfect, however i need create mail users that can use this format username@domain, but when i create a user with this format, i recived a error. This error say that only [A-Z][0-9]

Some Body know how i can do it????

[falko]

This is not possible with ISPConfig 2.