Well the thing is, for example following style declaration block:

div {
max-width: 100px;
*zoom: 1;
position: relative;
}

will result in

div {
max-width: 100px;
}

Which is wrong. At least in browser compliant mode. Just to give you the context to my issue.
However, the proposed solution works for me, because i only use it in the property, as you said. BUT: I'm nowhere sure this is the right way to do so, especially about the parser syntax i use here. That's why i'm quite happy that you took a look and maybe you have a better and cleaner solution in mind.
Currently, when the parser hits *zoom it is not detected as an IDENT and hence will finally throw the ParseException instyleDeclarationBlock() because the parsed token does not match the expected one (RBRACE then). And hence will drop everything until the RBRACE.
I don't think there's a need for something like "legacy mode", supporting these IE hacks again. But as i wrote in the issue report, dropping (in browser compliant mode) for these properties in question, should only happen on that specific property.
Btw. what do you mean by "browser compliant" variation?