I've searched for bug here, and found only this one id=653573, but it's not quite the same.

I'm using Ubuntu 10.04 - so I went on Ubuntu bugtracker first - and there it is - https://bugs.launchpad.net/ubuntu/+source/gnome-commander/+bug/333318

Then I've built 1.2.8.12 - and bug is still there.

Steps to Reproduce:

1) Ctrl-N to start new connection
2) Choose FTP(with login)
3) Check "Use Gnome Keyring Manager" option
4) Provide server and user names
5) Wait for it...

Actual Results:

The program 'gnome-commander' received an X Window System error.
This probably reflects a bug in the program.
The error was 'RenderBadPicture (invalid Picture parameter)'.
  (Details: serial 47004 error_code 158 request_code 148 minor_code 5)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
The program 'gnome-commander' received an X Window System error.
This probably reflects a bug in the program.
The error was 'RenderBadPicture (invalid Picture parameter)'.
  (Details: serial 47005 error_code 158 request_code 148 minor_code 26)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)
Segmentation fault

Expected Results:

It should've open seahorse password window - to ask my master password.

Build Date & Platform:

16.09.2011
Linux eugene-laptop 2.6.32-33-generic #72-Ubuntu SMP Fri Jul 29 21:08:37 UTC 2011 i686 GNU/Linux

Additional Builds and Platforms:

As you can see on Ubuntu bugtracker - it's 100% reproducable for all Ubuntu systems.
https://bugs.launchpad.net/ubuntu/+source/gnome-commander/+bug/333318 

I'm waiting to hear back from you. Ready to provide any information.=)