Problems with SuSE 8.2 sendmail

Hello list, we have upgraded our mail server to SuSE 8.2 this weekend and also installed the latest sendmail updates (sendmail-8.12.7-77.i586.rpm). Now we have a problem: each time a mail arrives where the sender's user name is quoted, eg. "Jürgen Mell" the header is re-written to <"Jürgen Mell" and then sendmail complains about an unbalanced '<' (which is true of course, the '>' is missing). Any ideas what to do about that? Thanks for any hints! Jürgen