ispcp-dovecot-mngr bug

[biologist]

Yesterday, I put ispCP into productive. It's working fine so far, but today I recognized, there a problem with dovecot and usernames, that contain an underscore-character. So finally I figured out, that isp-dovocot-mngr is the problem, as there's an regexp for the username, that doesn't include underscore. As it's possible to create mailadresses via ispCP that contain underscores, this is (imho) a bug (that can be easily fixed).