Strangeness adding IPP printers

[Bryan Maupin]

I'm using RHEL 5.6, cups-1.3.7-26.el5, and I'm seeing two strange things:
1. When adding an IPP printer in the format ipp://hostname/printers/name using lpadmin I cannot get the printer to be automatically shared.
2. When adding such printers with lpadmin, -o printer-is-shared=true seems to have no effect.

It doesn't seem to matter whether I use a hostname or an IP address, or whether or not I specify a port.  Other schemes don't seem to be affected (socket://, http://).  The printer itself has no effect; as you can see in the below examples I didn't even use real printers.

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com -P dell-dp5330.ppd && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared Yes

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com/printers -P dell-dp5330.ppd && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared Yes

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com/printers/test -P dell-dp5330.ppd && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared No

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com/printers/test -P dell-dp5330.ppd -o printer-is-shared=true && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared No

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com/printers/foo -P dell-dp5330.ppd && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared No

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com/printers/foo -P dell-dp5330.ppd -o printer-is-shared=true && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared No

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com/foo -P dell-dp5330.ppd && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared Yes

$ sudo /usr/sbin/lpadmin -p test -E -v ipp://example.com/foo/foo -P dell-dp5330.ppd && sudo grep Shared /etc/cups/printers.conf && sudo /usr/sbin/lpadmin -x test
Shared Yes