"Don't work" means I have a confirmed defect in the plugins screen of the dashboard.
In the future, mentioning the actual problem in the description is best practice, and attacking developers for changing something is not ideal either. Had you have tested 3.1, or any of your plugin users had tested 3.1, it would've been identified at the time and fixed.
As it is, The problem is that @ is unexpected input, and does not fit with the WordPres "standard" plugin header, whilst the plugin still "Works" it's just the author details are not read correctly, That being said, That style of headers is something worth while supporting, as it is, a very small percentage of plugins use it, which explains why it was missed in the testing.