Title page doesn't always display ISBN correctly, e.g. http://www.isfdb.org/cgi-bin/title.cgi?37602 displays "978-1-65526-4-" even though the associated Publication page (http://www.isfdb.org/cgi-bin/pl.cgi?TCHFSTRGN1987) displays "0-671-65526-4" correctly.
Anonymous
This is fixed by the 5-Jul-2009 commit of common/library.py. The routine responsible for converting the stored ISBN for display (in theory, punctuating it) was mistakenly referring to the length of the stored value, rather than the length of the "normalized" value. In this case, the ISBN-10 was stored with dashes in it (not normally done), and the resulting length was 13, causing it to be mis-treated as an ISBN-13. It will now be treated as the ISBN-10 that it actually is.
Fixed in r2009-08.