emacs 21 c-indent broken

[tl]

Hi, 

It seems that emacs 21.2.2 is confused when "case" and ":" are both
used inside a string; see my example in a c-mode buffer:

int
main()
{
    int res;
    printf("case A :\n");                                       
    printf("case B :\n");
                res = 0; /* indentation broken! */
}

I didn't have this problem this 21.7.1.

Any idea?

Cheers,
TL.