Description of problem:
-----------------------
for printers connected through samba, username and password in Device URI is
lost after apply changes using system-config-printer

Version-Release number of selected component (if applicable):
-------------------------------------------------------------
system-config-printer-0.7.49-1.fc6
system-config-printer-libs-0.7.49-1.fc6

How reproducible:
-----------------
It can always be reproduced.

Steps to Reproduce:
1. start system-config-printer
2. select a printer, say HPLaserJ, the Device URI in the right hand side is
protected field showing something like smb://…/myserver/HPLaserJ
(The DeviceURI in file /etc/cups/printers.conf for this printer is showing
something like smb://myuser:mypass@/myserver/HPLaserJ)
3. Change any other field, say click on the Enabled checkbox to change from on
to off.
4. Click the Apply button.
5. Look at the file /etc/cups/printers.conf, the line for DeviceURI for this
printer now showing something like smb://…/myserver/HPLaserJ
6. The Device URI field in the right hand side of system-config-printer becomes
a input capable field
7. The printer is not functioning because of authentication failure.
  
Actual results:
---------------
After applying any changes in system-config-printer, the "username:password" in
DeviceURI in /etc/cups/printers.conf is changed to "…"


Expected results:
-----------------
After applying any changes in system-config-printer, it should display the
Device URI as something like smb://…/myserver/HPLaserJ but it should not change
the DeviceURI in /etc/cups/printers.conf to something like
smb://…/myserver/HPLaserJ (it should keep it as
smb://myuser:mypass@/myserver/HPLaserJ)

Additional info: