In fact, it happens all the time.
And now that the project has opened its doors to code contributions from corporates, it is not surprising for Samba developers to receive code contributions from organisations big and small.
But one code contribution, made on October 10, represents a remarkable change.
As Samba team member Chris Hertel put it, "If you follow the Samba Technical Mailing List (and who doesn't, I mean really), you may have noted a patch submission that came in on October 10th, 2011.
"As often happens, a couple of developers at a company found a way to improve core Samba code. They got permission to submit the patches under their own copyright and the terms of the GPL, and they sent the patches in."
Samba is one of the free software projects that has moved in toto to the GPL version 3.
"It happens all the time in Samba, and we are always grateful. The only notable thing in this particular case is the company for which those developers work: Microsoft," Hertel added.
"A few years back, a patch submission from coders at Microsoft would have been amazing to the point of unthinkable, but the battles are mostly over and times have changed.
"We still disagree on some things such as the role of software patents in preventing the creation of innovative software; but Microsoft is now at the forefront of efforts to build a stronger community and improve interoperability in the SMB world.
He said most people did not even notice the source of the contribution. "That's how far things have come in the past four-ish years. But some of us saw this as a milestone, and wanted to make a point of expressing our appreciation for the patch and the changes we have seen."
The patches were sent in by Stephen Zarkos of the Microsoft Open Source Technology Centre. "Earlier this year we had an intern working with us to implement a proof of concept for extended protection (channel and service binding) for Firefox and Samba," he wrote.
"To enable this scenario on the client side, we were able to use libraries available on Windows and contribute code to the Mozilla team to make this all work. On the Linux side, however, Firefox utilizes (sic) Samba for NTLM authentication and so he also built some patches for Samba to enable this scenario.
Zarkos added; "These patches have been approved for release as 'GPLv2 or later' and copyright has been assigned to me (just like our build farm patches earlier). My only concern is that these patches may be bit stale and may need some work. Hopefully they are still useful to you and are not so huge that you can see what he was trying to do. The original developer (Guillermo Robla Vicario) may be able to assist a bit with questions, although he's no longer with MS and is quite busy these days :)
"Please let me know what you think. Also, for reference the Mozilla bug related to Guillermo's contribution to that team can be seen here: https://bugzilla.mozilla.org/show_bug.cgi?id=573043."