[NTG-context] Bibliographic entries

Dear ConTeXt experts, I have a question about bibliographic entries and I'm using ConTeXt bib module (which is really great!!). I have an article with a title that ends in a question mark. When the entry is typeset an additional period is placed at the end of the article via the \insertarttitle{ \bgroup``}{.'' \egroup}{} command. Is there an easy way to adjust the \insertarttitle command so that if the last character of the title entry in the bib-file is a punctuation character (say ! or ?), then we do not append a period? Thanks in advance for any suggestions. Best regards, Ernesto