portupgrade not preserving shared libs as documented?

[Cstdenis]

Portupgrade man page says "By default, portupgrade preserves shared 
libraries on uninstallation for safety."

I ran i in the form of: portupgrade -b pcre

Now /usr/local/lib/libpcre.so.0 does not exist anymore, only the new 
/usr/local/lib/libpcre.so.1 is there.