What version of CssMin are you using (source and/or build)?
    version 3.0.1

What was the input stylesheet and/or configuration options?
    Input:  @media(max-width:767px)

What is the expected result?
    Output: @media(max-width:767px)

And what is the actual result and/or error message?
    @media max-width:767px)

Please provide any additional information below.
   http://code.google.com/p/cssmin/source/browse/trunk/source/parser/plugins/CssAtMediaParserPlugin.php#54
   This line ignored the first "(" so if i dump the part, you can see the "(" is missing in MediaTypes.

[XX] => CssRulesetDeclarationToken(
    MediaTypes = array(
        [0] => 'max-width:767px)'
    )
    IsImportant = FALSE
    IsLast = TRUE
    Property = 'width'
    Value = 'auto'
)