BUG: CSS counters

I have a stylesheet using the CSS2 counter syntax:

table.eventList
{
    counter-reset: day-item;
}
table.eventList tbody td.counter span:before
{
    content: counter(day-item, lower-roman);
    counter-increment: day-item;
}

R# flags the comma in "counter(day-item, lower-roman)" as an error: "Expected one of: disc, circle, ...", but the style works as expected.

If I change the style to "counter(day-item lower-roman)", R# is happy but the style doesn't work.

Is this a known problem or a new bug?

ReSharper 7.1.1 Full Edition Build 7.1.1000.900
Visual Studio 2012 Professional
Windows 7 x64